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Nopparat, Nanond, und Babak Kianian. „Resource Consumption of Additive Manufacturing Technology“. Thesis, Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3919.
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The degradation of natural resources as a result of consumption to support the economic growth of humans society represents one of the greatest sustainability challenges. In order to allow economic growth to continue in a sustainable way, it has to be decoupled from the consumption and destruction of natural resources. This thesis focuses on an innovative manufacturing technology called additive manufacturing (AM) and its potential to become a more efficient and cleaner manufacturing alternative. The thesis also investigates the benefits of accessing the technology through the result-oriented Product-Service Systems (PSS) approach. The outcome of the study is the quantification of raw materials and energy consumption. The scope of study is the application of AM in the scale model kit industry. The methods used are the life cycle inventory study and the system dynamics modeling. The result shows that AM has higher efficiency in terms of raw material usage, however it also has higher energy consumption in comparison to the more traditional manufacturing techniques. The result-oriented PSS approach is shown to be able to reduce the amount of manufacturing equipment needed, thus reducing the energy and raw materials used to produce the equipment, but does not completely decouple economic growth from the consumption of natural resources.
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Sandell, Malin, und Saga Fors. „Design for Additive Manufacturing - A methodology“. Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-263134.
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Additive manufacturing (AM), sometimes called 3D-printing is a group of manufacturing technologies that build up a product using a layer by layer technique and provides new ways of manufacturing parts and products. The Company in this thesis wants to make AM a tool in their manufacturing toolbox. When introducing this manufacturing method, new processes and methods have to be developed. The purpose of this thesis is to develop a methodology that will help the designers when identifying parts that should be manufactured using AM. The development of this methodology has followed the principles of service design which is a holistic interdisciplinary approach where methods from different disciplines are combined to create benefits to the end user experience. Before the development process, a large background study was performed to gather detailed information within the area of AM. The methodology concept was then developed through five iterative cycles where methods such as interviews, trigger material, questionnaire, case study and stakeholder mapping were used. The thesis resulted in an AM handbook with information regarding the technology and a five step methodology for choosing when and why to use AM as a manufacturing method. Step one is to identify the AM potential in a product which is based on complexity, customization and production volume. Step two is to specify requirements of the products, this can be surface finish, tolerances etc. The third step in the design methodology is part screening, which is the making of the final decision about if the product should be printed and if it can be printed. The fourth step is to choose an AM technology based on the requirements specified in step two by providing information about the technologies’ restrictions and possibilities. Step five in this methodology is the design of AM products and provides simple design guidelines. It has been shown that a dynamic task is best solved through working with dynamic methods, therefore service design approach is a flexible and good fit for this thesis. This design methodology is only a part of the AM-area and needs to be supplemented with other knowledge within the area. The first step after implementing this handbook is to investigate how the organization and business is affected when implementing AM.Additiv tillverkning (AM), även kallat 3D-printing, är benämningen på en grupp tillverkningstekniker där en produkt byggs lager för lager. Denna masteruppsats har utförts i samarbete med ett svenskt industriföretag som levererar lösningar inom tillverkningsindustrin, i rapporten kallat Företaget. Genom att utveckla nya designprocesser och metoder vill Företaget inkludera AM i sin tillverkningsstrategi. Syftet med detta masterexamensarbete var att utveckla en metodik för hur urval och utveckling av produkter anpassade för AM ska ske. Utvecklingen av metodiken följer principerna för tjänstedesign, vilket innebär ett holistiskt tvärvetenskapligt arbetssätt där metoder från olika discipliner kombineras för att skapa en positiv upplevelse för slutanvändaren. Innan utvecklingsprocessens start gjordes en stor bakgrundsstudie för att införskaffa kunskaper kring AM. Därefter utvecklades en metod genom fem iterativa cykler där metoder som intervjuer, triggermaterial, frågeformulär, fallstudier och stakeholdermapping användes. Masteruppsatsen resulterade i en handbok med information kring teknikerna och en metodik i fem steg för att välja när och varför AM bör användas som tillverkningsmetod. Första steget är att identifiera AM potentialen hos en produkt, vilket baseras på komplexitet, kundanpassning och produktionsvolym. I steg två ska produktkrav specificeras, exempel på sådana krav är ytfinhet och toleranser. Tredje steget i metoden handlar om en produkt-undersökning under vilken ett slutgiltigt beslut fattas angående om produkten kan och bör tillverkas. I fjärde steget sker valet av teknik baserat på de produktkrav som specificerats i steg två, genom att information ges angående teknikens möjligheter och begränsningar. Femte steget i metoden handlar om designen av AM produkter och förser konstruktören med enklare riktlinjer för designen. Utveckling av en metodik kräver ett dynamiskt arbetssätt och principerna inom service design visade sig passa bra för detta projekt. Det visade sig också att den resulterade metodik behöver kompletteras med information i framtiden. Det behövs även fastställas tydliga mål för AM i företaget och vilket syfte implementeringen av denna nya process innebär
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Martens, Robert. „Strategies for Adopting Additive Manufacturing Technology Into Business Models“. ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/5572.
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Additive manufacturing (AM), also called 3-dimensional printing (3DP), emerged as a disruptive technology affecting multiple organizations' business models and supply chains and endangering incumbents' financial health, or even rendering them obsolete. The world market for products created by AM has increased more than 25% year over year. Using Christensen's theory of disruptive innovation as a conceptual framework, the purpose of this multiple case study was to explore the successful strategies that 4 individual managers, 1 at each of 4 different light and high-tech manufacturing companies in the Netherlands, used to adopt AM technology into their business models. Participant firms originated from 3 provinces and included a value-added logistics service provider and 3 machine shops serving various industries, including the automotive and medical sectors. Data were collected through semistructured interviews, member checking, and analysis of company documents that provided information about the adoption of 3DP into business models. Using Yin's 5-step data analysis approach, data were compiled, disassembled, reassembled, interpreted, and concluded until 3 major themes emerged: identify business opportunities for AM technology, experiment with AM technology, and embed AM technology. Because of the design freedom the use of AM enables, in combination with its environmental efficiency, the implications for positive social change include possibilities for increasing local employment, improving the environment, and enhancing healthcare for the prosperity of local and global citizens by providing potential solutions that managers could use to deploy AM technology.
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Prakash, Shyam Geo. „Application Based Design for Additive Manufacturing : Development of a systematic methodolgy for part selection and design for Additive Manufacturing“. Thesis, KTH, Industriell produktion, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-287190.
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Additive manufacturing (AM) is a forthcoming technology which has received much attention during recent decades and is currently on its journey from prototype to small scale production. The final component is made layer upon layer, hence bringing wider opportunities such as design freedom, flexibility, and optimal material usage, etc. Rapid advancements in AM technology in terms of speed, dimensional accuracy, surface finish and repeatability, enable production of functional end use parts in tolerable volume. The research is conducted in cooperation with Atlas Copco Industrial Technique (ACIT) to explore the path towards using AM as a tool for low volume production. Currently, AM technology is widely used for prototyping at ACIT. Therefore, the purpose of the thesis project is to investigate and recommend a design methodology and guidelines for shifting from prototype to small scale production through AM. However, introduction of AM in small scale manufacturing requires its consideration right from the initial stage of product development. Initially, a thorough background study was done to understand the AM technology and its current advancement with respect to technology maturity and market aspects. The background study includes literature review, market study, interviews, visits to AM service providers, AM exhibitions, etc. Market research aided the study to be focused on two technologies i.e. Selective Laser Melting and Binder Jetting. Due to current limitations of AM technology, not all parts are good candidates to exploit the potential in AM. Considering this, questionnaires were prepared based on the literature study which was later used to get the potential part candidates for AM from mechanical designers at Research and Development, Nacka. The proposed part screening methodology categorizes parts by three main driving criteria and further leads to a technical and economical evaluation. Through bottom up approach for part screening, parts with highest potential in AM were identified and redesigned, facilitating AM conformal designs. Moreover, the parts were further utilised to propose design methodology and guidelines that could aid designers in designing parts for AM. The design methodolgy involves four stages including information phase, assessment phase, design phase and detail design phase. The thesis project resulted in selection and redesign of components with potential in AM while adding values through part consolidation, light weight design using topology optimisation and cost reduction, etc. The earlier the consideration of manufacturing technology in thedevelopment phase, the better the final design in terms of manufacturability. With respect to AM, this is a very crucial aspect, as complexity comes with almost no cost. Therefore, a simulation driven design process in which one starts the development with an optimised concept or concept designed for function can be manufactured thus leveraging the benefits of AM.Additiv tillverkning (AT) är en tillgänglig teknologi som har fått mycket uppmärksamhet under de senaste decennierna och som för närvarande är på väg från prototypappliceringar till småskalig produktion. Den slutgiltiga komponenten är framställd genom att addera lager på lager och medför därmed vida möjligheter såsom designfrihet, flexibilitet och optimal materialanvändning, etc. Med anledning av snabba tekniska framsteg inom AT vad gäller hastighet, dimensionell noggrannhet, ytfinish och repeterbarhet, möjliggörs produktion av funktionella slutprodukter i tolerabla volymer. Forskningen är genomförd i samarbete med Atlas Copco Industriell Teknik (ACIT) med syfte att utforska vägen mot användning av AT som ett verktyg vid låga produktionsvolymer. I nuläget används AT flitigt för att skapa prototyper inom ACIT. Syftet med detta masterprojekt är därför att undersöka och rekommendera en designmetodik samt riktlinjer för att skifta från prototypappliceringar till småskalig produktion med AT. Emellertid kräver en introduktion av AT för småskalig produktion eftertanke redan i de inledande stadierna av produktutvecklingen. Till att börja med utfördes en grundlig bakgrundstudie för att omfatta AT som teknologi och dess nuvarande framsteg med avseende på teknologisk mognad och marknadsaspekter. Bakgrundsstudien innehåller litteraturstudie, marknadsstudie, intervjuer, besök hos tjänsteleverantörer av AT, utställningar med fokus på AT, etc. Marknadsundersökningen understödde ett fokus av studien mot två teknologier, nämligen Selektiv Lasersmältning (Selective Laser Melting) och Bindemedelstrålning (Binder Jetting). Med anledning av dagens begränsningar inom AT är inte alla typer av komponenter passande kandidater för att undersöka potentialen av teknologin. Med detta i beaktande förbereddes frågeformulär, baserade på litteraturstudien, som sedan användes för att med hjälp av mekaniska designers vid R&D i Nacka, identifiera potentiella komponenter att använda för AT. Den föreslagna metodiken för att undersöka komponenter kategoriserar komponenter genom tre drivande kriterier och leder i därefter till en teknisk och ekonomisk utvärdering. Genom en bottom-up approach för undersökande av komponenter, identifieras och omdesignas komponenter med högst potential för AT, vilket främjar en lämplig design för AT. Dessutom användes dessa komponenter för att föreslå en designmetodik samt riktlinjer som kan vara till hjälp för designers vid design av komponenter för AT. Designmetodiken innefattar följande fyra steg: informationsfas, bedömningsfas, designfas och detaljerad designfas. Masterprojektet resulterade i val och omdesign av komponenter med potential för AT samtidigt med värdeaddering genom sammanslagning av komponenter, design med lätt vikt genom optimering av topologi och kostnadsminskning, etc. Ju tidigare beaktande av produktionsmetod i utvecklingsfasen, desto bättre slutdesign med avseende på producerbarhet. Detta är en kritisk aspekt när det kommer till AT, eftersom komplexitet nästintill adderas kostnadslöst. Därför kan en simulationsdriven designprocess, i vilken utvecklingen börjar med ett optimerat koncept eller ett koncept designat för funktion, komma i produktion och maximalt utnyttja fördelarna av AT.
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Lebherz, Matthias, und Jonathan Hartmann. „Commercializing Additive Manufacturing Technologies : A Business Model Innovation approach to shift from Traditional to Additive Manufacturing“. Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-36132.
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Additive Manufacturing is a fast-developing technology that is considered to be a game changer in the manufacturing industry. However, a technological innovation itself has no single objective value for a company. Indeed, it is widely acknowledged that the key aspect of a successful commercialization of a technological innovation is the linkage of the technology and the business model. Based on a qualitative study, which presents how companies have to develop their business model to commercialize AM, we conducted interviews with two Swedish small and medium-sized enterprises, which plan to invest in Additive Manufacturing. These two companies are HGF, a manufacturer of thermoplastic elastomers and rubber products, and Tylö, a manufacturer of heaters, steam generators, saunas, steam showers, and infrared saunas. In our analysis, we decided to analyse the cases successively, according to the nine building blocks of the Business Model Canvas. Firstly, we conducted a within-case analysis to analyse each case isolated from each other, and secondly a cross-case analysis to find possible nexuses, relations or, contrasts. The chapter conclusion provides an overall discussion of the most important findings emerging from the analysis with regard to the required changes within the current business model to capture value from the technology. We could find some disparities for two building blocks (channels and revenue streams). Thus, this implies that there is no universal approach to develop the business model to introduce Additive Manufacturing. Nevertheless, most of the required adjustments show accordance. While three building blocks turned out to remain largely the same (key partnerships, cost structure, and customer segments), four building blocks require important changes (key activities, key resources, value propositions, and customer relationships. The most important implications for those building blocks are presented in the following: Key activities: Upgrade product development Key resources: Establish additional production facilities (3D-printers, etc.) Gather new knowledge about AM Value propositions: Offer customized products Customer relationships: Closer relationship with the (end) customer Enhance customer co-creation
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Margolin, Lauren. „Ultrasonic Droplet Generation Jetting Technology for Additive Manufacturing: An Initial Investigation“. Thesis, Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14031.
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Additive manufacturing processes, which utilize selective deposition of material rather than traditional subtractive methods, are very promising due to their ability to build complex, highly specific geometries in short periods of time. Three-dimensional direct inkjet printing is a relatively new additive process that promises to be more efficient, scalable, and financially feasible than others. Due to its novelty, however, numerous technical challenges remain to be overcome before it can attain widespread use. This thesis identifies those challenges and finds that material limitations are the most critical at this point. In the case of deposition of high viscosity polymers, for example, it is found that droplet formation is a limiting factor.
Acoustic resonance jetting, a technology recently developed at Georgia Institute of Technology, may have the potential to address this limitation because it generates droplets using a physical mechanism different from those currently in use. This process focuses ultrasonic waves using cavity resonances to form a standing wave with high pressure gradients near the orifice of the nozzle, thereby ejecting droplets periodically. This thesis reports initial exploratory testing of this technologys performance with various material and process parameters. In addition, analytical and numerical analyses of the physical phenomena are presented. Results show that, while the pressures generated by the system are significant, energy losses due to viscous friction within the nozzle may prove to be prohibitive. This thesis identifies and begins evaluation of many of the process variables, providing a strong basis for continued investigation of this technology.
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Dash, Satabdee. „Design for Additive Manufacturing : An Optimization driven design approach“. Thesis, KTH, Maskinkonstruktion (Inst.), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-281246.
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Increasing application of Additive Manufacturing (AM) in industrial production demands product reimagination (assemblies, subsystems) from an AM standpoint. Simulation driven design tools play an important part in achieving this with design optimization subject to the capabilities of AM technologies. Therefore, the bus frames department (RBRF) in Scania CV AB, Södertälje wanted to examine the synergies between topology optimization and Design for AM (DfAM) in the context of this thesis. In this thesis, a methodology is developed to establish a DfAM framework involving topology optimization and is accompanied by a manufacturability analysis stage. A case study implementation of this developed methodology is performed for validation and further development. The case study replaces an existing load bearing cross member with a new structure optimized with respect to weight and manufacturing process. It resulted in a nearly self supporting AM friendly design with improved stiffness along with a 9.5% weight reduction, thereby proving the benefit of incorporating topology optimization and AM design fundamentals during the early design phase.Ökad användning av Additive Manufacturing (AM) i industriell produktion kräver ett nytänkade av produkter (enheter, delsystem) ur AM-synvinkel. Simuleringsdrivna designverktyg spelar en viktig roll för att nå detta med designoptimering med hänsyn taget till AM-teknikens möjligheter. Därför ville bussramavdelningen (RBRF) på Scania CV AB, Södertälje undersöka synergierna mellan topologioptimering och Design för AM (DfAM) i detta examensarbete. I examensarbetet utvecklas en metodik för att skapa en DfAM-ramverk som involverar topologioptimering och åtföljs av ett tillverkningsanalyssteg. En fallstudieimplementering av denna utvecklade metodik utförs för validering och fortsatt utveckling. Fallstudien ersätter en befintlig lastbärande tvärbalk med en ny struktur optimerad med avseende på vikt och tillverkningsprocess. Det resulterade i en nästan självbärande AM-vänlig design med förbättrad styvhet tillsammans med en viktminskning på 9,5 %, vilket visar fördelen med att integrera topologioptimering och grundläggande AM-design tidigt i designfasen.
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Margolin, Lauren. „Ultrasonic droplet generation jetting technology for additive manufacturing an initial investigation /“. Available online, Georgia Institute of Technology, 2006, 2007. http://etd.gatech.edu/theses/available/etd-10252006-094048/.
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Egan, M. J. „Spiral growth manufacture : a continuous additive manufacturing technology for powder processing“. Thesis, University of Liverpool, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491352.
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Layered manufacturing (LM) technologies are a class of additive manufacturing processes which create three dimensional geometries directly from CAD data sequentially layer by layer. This group of technologies can process a variety of metallic, polymer and ceramic materials, as liquids, powders, or solid sheets or filaments. The material can be processed using a laser, such as melting a powder or curing a polymer resin or consolidated using a binder deposited from a print head. The build methodology used in all LM is fundamentally a start-stop process since the deposition of material and processing of each layer occurs ~equentially. Hence, the build rate can be slow (2 - 6 Layers per minute); consequently, LM technologies have largely found application as prototyping tools to speed up product development. In order for these technologies to be adopted as rapid manufacturing (RM) methods to directly manufacture complex components which cannot be manufactured by other means these speed limitations need to be addressed. This Thesis describes a new high speed RM process, Spiral Growth Manufacturing (SGM), whereby 3D parts are built by simultaneously depositing, levelling and selectively consolidating thin powder layers onto a rotating build platform. This build configuration has several advantages when compared to conventional layered manufacturing systems: firstly, the process is continuous with no layer preparation overheads; secondly, the material deposition and solidification process can be performed simultaneously by the addition of further 'build stations' radially distributed about the circumference of the machine. The work presented in this thesis focused on the design, development and testing ofthe Spiral Growth Manufacturing process. Two machines were developed; one used a bank of stationary inkjet heads to print material, either as a binder into a powder layer or as hard material from mixing two printed ink solutions and the other machine used a 90 W, flash lamp pumped Nd:YAG laser to process metal powders by localised melting. The main objective ofthe testing phase was to produce simple 3D objects from solidified layers by: a) ink jet printing a binding agent into the deposited plaster powder layers; and b) ink jet printing reactive materials to form plaster directly. The second machine was developed to exploit the considerable knowledge of Selective Laser Melting (SLM) at Liverpool, with the modification of a research SLM machine to SGM operation.
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Parimi, Lakshmi Lavanya. „Additive manufacturing of nickel based superalloys for aerospace applications“. Thesis, University of Birmingham, 2014. http://etheses.bham.ac.uk//id/eprint/4982/.
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The aim of this work is to establish the influence of the many process variables on the microstructure and the nature of internal stress in IN718 samples produced directly from powder using direct laser fabrication, which enables production of solid samples directly from a CAD file. The process variables that have been studied include, specimen geometry, laser power, laser traverse speed, the detailed laser path and powder feed rate. It has been found that the detailed microstructure is strongly influenced by all of these variables with the propensity for the production of equiaxed or columnar grains being strongly influenced by laser power. The texture is correspondingly strongly influenced by changes in processing conditions. The extent of precipitation of the various phases expected in IN718 was also found to be influenced by the process conditions. The level and nature of the residual stress in the sample and in the substrate have been determined for a wide range of experimental conditions and using neutron diffraction. It has been found that the level of these stresses could be reduced to a minimum value of about 300 MPa, but could not be eliminated. A simple 3D thermo-mechanical model was developed to understand the residual stress distribution, which agreed closely with the experimental measurements.
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Philip, Ragnartz, und Axel Staffanson. „Improving the product development process with additive manufacturing“. Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-40344.
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The following report consists of a master thesis (30 credits) within product development. The thesis is written by Philip Ragnartz and Axel Staffanson, both studying mechanical engineering at Mälardalens University. Developing new components for a production line is costly and time consuming as they must be made from manual measurements and must go through all the conventional manufacturing (CM) steps. Eventual design mistakes will be discovered after the component have been manufactured and tested. To fix the design a completely new component must be designed and therefore double the overall lead time. The purpose of this thesis is to establish how additive manufacturing (AM) can best be used to minimize the cost and lead time in the development of new components. The study was performed by looking at the current product development process in the automotive industry at a large company, here by referred to as company A. 56 components already manufactured at company A´s own tools department was examined and compared to different AM methods. The aim of this was to get a larger pool of data to get an average on production time and cost and see how this differ to the different AM methods. Additionally, two work holders were more closely examined in a case study. Work holder one is a component in the production line that occasionally must be remanufactured. It was examined if this problem could be solved with a desktop plastic printer to hold up for a production batch. Work holder two was the development of a new component, this was to examine the use of printing the component in an early stage impact the development process. The findings from this study is that AM can today not be used in a cost efficient way in manufacturing or development of simple components. This is due to the cost of a metal 3D-printer is still very high, and the building material even higher. This results in components that gets very expensive to make compared to producing them with CM. For design evaluation to be cost efficient there will have to be a design fault in over 12 % of the newly design components for it to be cost effective to print the design for validation before sending it to be manufactured. There are however a lot bigger potential savings in the lead time. Producing the end product with a metal 3D-printer can cut down the lead time up to 85 %. This is thanks to the fact that the printer will produce the component all in one step and therefore not get stuck in between different manufacturing processes. The same goes for design evaluation with printing the component in plastic to confirm the design and not risk having to wait for the component to be manufactured twice. Despite the facts that it is not cost efficient to use AM there are other factors that play an important role. To know that the designed components will work will create a certainty and allow the development process to continue. In some cases it will also allow the designer to improve the design to function better even if the first design would have worked. As AM is expanding machines and build materials will become cheaper. Eventually it will become cheaper to 3D-print even simple components compared to CM. When this occurs, a company cannot simply buy a 3D-printer and make it profitable. There is a learning curve with AM that will take time for the designers to adapt to. Therefore, it is good to start implementing it as soon as possible as it allows for more intricate designs and require experience to do so.
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Jansson, Anton, und Oscar Edholm. „Scale factor and shrinkage in additive manufacturing using binder jetting“. Thesis, KTH, Materialvetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-190064.
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Abdul, Kudus Syahibudil I. „The value of personalised consumer product design facilitated through additive manufacturing technology“. Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/34616.
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This research attempted to discover how Additive Manufacturing (AM) can best be used to increase the value of personalised consumer products and how designers can be assisted in finding an effective way to facilitate value addition within personalisable product designs. AM has become an enabler for end-users to become directly involved in product personalisation through the manipulation of three-dimensional (3D) designs of the product using easy-to-use design toolkits. In this way, end-users are able to fabricate their own personalised designs using various types of AM systems. Personalisation activity can contribute to an increment in the value of a product because it delivers a closer fit to user preferences. The research began with a literature review that covered the areas of product personalisation, additive manufacturing, and consumer value in product design. The literature review revealed that the lack of methods and tools to enable designers to exploit AM has become a fundamental challenge in fully realising the advantages of the technology. Consequently, the question remained as to whether industrial designers are able to identify the design characteristics that can potentially add value to a product, particularly when the product is being personalised by end-users using AM-enabled design tools and systems. A new value taxonomy was developed to capture the relevant value attributes of personalised AM products. The value taxonomy comprised two first-level value types: product value and experiential value. It was further expanded into six second-level value components: functional value, personal-expressive value, sensory value, unique value, co-design value, and hedonic value. The research employed a survey to assess end-users value reflection on personalised features; measuring their willingness to pay (WTP) and their intention to purchase a product with personalised features. Thereafter, an experimental study was performed to measure end-users opinions on the value of 3D-printed personalised products based on the two value types: product value and experiential value. Based on the findings, a formal added value identification method was developed to act as a design aid tool to assist designers in preparing a personalisable product design that embodies value-adding personalisation features within the product. The design method was translated into a beta-test version paper-based design workbook known as the V+APP Design Method: Design Workbook. The design aid tool was validated by expert designers. In conclusion, this research has indicated that the added value identification method shows promise as a practical and effective method in aiding expert designers to identify the potential value-adding personalisation features within personalisable AM products, ensuring they are able to fully exploit the unique characteristics and value-adding design characteristics enabled by AM. Finally, the limitations of the research have been explained and recommendations made for future work in this area.
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Nguyen, Theresa Hoai-Thuong. „ADDITIVE MANUFACTURING FOR ASSISTIVE TECHNOLOGY : Innovative Design for an Ankle Foot Orthosis“. Thesis, Jönköping University, JTH, Industridesign, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-51593.
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The following report presents a Master thesis project about a re-design of an ankle foot orthosis using additive manufacturing as the production method, conducted by a student in Spring 2020 as part of the Master’s programme Industrial Design at Jönköping University’s School of Engineering. Ankle foot orthoses are the most prescribed lower extremity orthoses worldwide and are worn in a visually obtrusive way making patients feel stigmatized for their disability. The social stigma makes it emotionally difficult for many users to wear an AFO frequently enough for proper rehabilitation. Despite its significance and wide spread use, its design has not changed for over 50 years. Traditional manufacturing methods are difficult to work with and make customization options very limited. By using digital additive manufacturing methods like 3D Scanning, 3D printing and computer simulations, it is possible to offer personalized looks for AFOs by implementing almost any custom pattern expressed in cut-outs on the AFO surface. That kind of perforation simultaneously solves the problem of bad perspiration and air flow. The freedom of graphical expression in those patterns invite the patient to participate in the design process themselves to create an ankle foot orthosis that is their own. That revolutionary twist on the manufacturing and design process empowers the user to take control over their disability to the furthest degree possible and returns the human right of self-determination and independence to them.Följande rapport presenterar ett examensarbete gällade en omdesign av en ankel-fot-ortos med additiv tillverkning som produktionsmetod, genomförd av en student våren 2020 som del av masterprogrammet Industrial Design vid Jönköpings universitets tekniska högskola. Ortoser för fotleden är de mest föreskrivna ortoserna för underkroppen i hela världen och bärs på ett visuellt påträngande sätt vilket gör att patienterna kan känna sig annorlunda eller utanför för sin funktionsnedsättning. Den sociala stigmatiseringen gör det känslomässigt svårt för många användare att bära en AFO ofta nog för korrekt rehabilitering. Trots dess betydelse och breda användning har designen inte förändrats på över 50 år. Traditionella tillverkningsmetoder är svåra att arbeta med och begränsar alternativen för anpassning. Genom att använda digitala metoder för additiv tillverkning som 3D-skanning, 3D-utskrift och datorsimuleringar är det möjligt att erbjuda ett personligt utseende för AFO genom att införa en stor mängd anpassade mönster i form av utskärningar på AFO-ytan. Denna typ av perforering löser samtidigt problemet med svett och dåligt luftflöde. Friheten för grafiskt uttryck genom dessa mönster låter patienten delta i själva designprocessen för att fotledsortosen ska kännas som deras egen. Detta nya synsätt på utveckling på tillverknings- och designprocessen gör det möjligt för användaren att ta kontroll över sin funktionsnedsättning i största möjliga grad och återställer känslan av självständighet.
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Lopes, Ana Isabel Mira. „Additive manufacturing adoption in portuguese companies : case study analysis“. Master's thesis, Instituto Superior de Economia e Gestão, 2019. http://hdl.handle.net/10400.5/19200.
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Mestrado em Gestão e Estratégia IndustrialAo longo dos anos, a manufatura aditiva tem estado em constante desenvolvimento e tem mostrado ser verdadeiramente uma tecnologia de produção. No entanto, embora não seja uma tecnologia nova, ainda carece de investigação e, portanto, com a sua crescente aceitação torna-se relevante estender a literatura sobre o tema, daí o objetivo deste estudo exploratório ser a análise da adoção da manufatura aditiva em empresas portuguesas. Os resultados parecem mostrar que as motivações para a adoção da manufatura aditiva são influenciadas maioritariamente por fatores estratégicos e tecnológicos, e que o principal desafio é a falta geral de conhecimento sobre a tecnologia. Os resultados também mostram que todas as empresas entrevistadas experienciaram benefícios em capacidade de autonomia, curto tempo de colocação no mercado de novos produtos, flexibilidade de produção, liberdade de design, capacidade de alto nível de customização, aumento da competitividade da empresa, aumento na inovação de produtos e processos, capacidade de alcançar novos clientes e envolvimento dos clientes no processo de criação. Quanto às limitações, as identificadas por todas as empresas foram a baixa taxa de produção oferecida pela tecnologia e a falta geral de conhecimento. No que respeita às perspetivas para o futuro, os resultados indicam que todas as empresas reconheceram que o potencial da tecnologia é imensurável, contudo mostra-se ainda necessário aumentar a oferta de educação e formações em manufatura aditiva, elevar a consciencialização acerca desta tecnologia, melhorar a velocidade e a qualidade da impressão, progredir no desenvolvimento de tecnologias híbridas e aumentar a certificação.
Throughout the years, additive manufacturing has been in constant development and has been proving itself to be a true production technology. However, even though it is not a new technology, it still lacks research, and therefore, with its increased acceptance it becomes relevant to enlarge academic literature on the theme, hence the purpose of this exploratory study being the research on the adoption of additive manufacturing in Portuguese companies. The findings appear to show that motivations for additive manufacturing adoption are mostly influenced by strategic and technological factors, and that the main challenge is the general lack of knowledge about the technology. The findings also show that all interviewed companies have experienced benefits in autonomous abilities, short time-to- market of new products, production flexibility, design freedom, capabilities of high-level customization, increase in the company's competitiveness, boost in product and processes' innovation, capability of reaching new customers and customer involvement in the creation process. As for limitations, the ones identified by all companies were the short production rate offered by the technology and the general lack of knowledge. Regarding prospects for the future, findings show that all companies recognized that the technology's potential is unmeasurable, however there is still a need to increase the offer in additive manufacturing education and trainings, spread awareness of this technology, improve printing speed and quality, progress in the development of hybrid technologies and increase certification.
info:eu-repo/semantics/publishedVersion
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Kumara, Chamara. „Microstructure Modelling of Additive Manufacturing of Alloy 718“. Licentiate thesis, Högskolan Väst, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-13197.
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In recent years, additive manufacturing (AM) of Alloy 718 has received increasing interest in the field of manufacturing engineering owing to its attractive features compared to those of conventional manufacturing methods. The ability to produce complicated geometries, low cost of retooling, and control of the microstructure are some of the advantages of the AM process over traditional manufacturing methods. Nevertheless, during the building process, the build material undergoes complex thermal conditions owing to the inherent nature of the process. This results in phase transformation from liquid to solid and solid state. Thus, it creates microstructural gradients in the built objects, and as a result,heterogeneous material properties. The manufacturing process, including the following heat treatment that is used to minimise the heterogeneity, will cause the additively manufactured material to behave differently when compared to components produced by conventional manufacturing methods. Therefore, understanding the microstructure formation during the building and subsequent post-heat treatment is important, which is the objective of this work. Alloy 718 is a nickel-iron based super alloy that is widely used in the aerospace industry and in the gas turbine power plants for making components subjected tohigh temperatures. Good weldability, good mechanical properties at high temperatures, and high corrosion resistance make this alloy particularly suitablefor these applications. Nevertheless, the manufacturing of Alloy 718 components through traditional manufacturing methods is time-consuming and expensive. For example, machining of Alloy 718 to obtain the desired shape is difficult and resource-consuming, owing to significant material waste. Therefore, the application of novel non-conventional processing methods, such as AM, seems to be a promising technique for manufacturing near-net-shape complex components.In this work, microstructure modelling was carried out by using multiphase-field modelling to model the microstructure evolution in electron beam melting (EBM) and laser metal powder directed energy deposition (LMPDED) of Alloy 718 and x subsequent heat treatments. The thermal conditions that are generated during the building process were used as input to the models to predict the as-built microstructure. This as-built microstructure was then used as an input for the heat treatment simulations to predict the microstructural evolution during heat treatments. The results showed smaller dendrite arm spacing (one order of magnitude smaller than the casting material) in these additive manufactured microstructures, which creates a shorter diffusion length for the elements compared to the cast material. In EBM Alloy 718, this caused the material to have a faster homogenisation during in-situ heat treatment that resulting from the elevated powder bed temperature (> 1000 °C). In addition, the compositional segregation that occurs during solidification was shown to alter the local thermodynamic and kinetic properties of the alloy. This was observed in the predicted TTT and CCT diagrams using the JMat Pro software based on the predicted local segregated compositions from the multiphase-field models. In the LMPDED Alloy 718 samples, this resulted in the formation of δ phase in the interdendritic region during the solution heat treatment. Moreover, this resulted in different-size precipitation of γ'/γ'' in the inter-dendritic region and in the dendrite core. Themicro structure modelling predictions agreed well with the experimental observations. The proposed methodology used in this thesis work can be an appropriate tool to understand how the thermal conditions in AM affect themicro structure formation during the building process and how these as-built microstructures behave under different heat treatments.
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Nyembwe, Kasongo Didier. „Tool manufacturing by metal casting in sand moulds produced by additive manufacturing processes“. Thesis, Bloemfontein : Central University of Technology, Free State, 2012. http://hdl.handle.net/11462/162.
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Thesis (D. Tech. ( Mechanical Engineering )) - Central University of technology, Free State, 2012In this study an alternative indirect Rapid Tooling process is proposed. It essentially consists of producing sand moulds by Additive Manufacturing (AM) processes followed by casting of tools in the moulds. Various features of this tool making method have been investigated. A process chain for the proposed tool manufacturing method was conceptually developed. This process chain referred to as Rapid Casting for Tooling (RCT) is made up of five steps including Computer Aided Design (CAD) modeling, casting simulation, AM of moulds, metal casting and finishing operations. A validation stage is also provided to determine the suitability of the tool geometry and material for RCT. The theoretical assessment of the RCT process chain indicated that it has potential benefits such as short manufacturing time, low manufacturing cost and good quality of tools in terms of surface finish and dimensional accuracy. Focusing on the step of AM of the sand moulds, the selection of available AM processes between the Laser Sintering (LS) using an EOSINT S 700 machine and Three Dimensional Printing using a Z-Corporation Spectrum 550 printer was addressed by means of the Analytic Hierarchy Process (AHP). The criteria considered at this stage were manufacturing time, manufacturing cost, surface finish and dimensional accuracy. LS was found to be the most suitable for RCT compared to Three Dimensional Printing. The overall preferences for these two alternatives were respectively calculated at 73% and 27%. LS was then used as the default AM process of sand moulds in the present research work. A practical implementation of RCT to the manufacturing of foundry tooling used a case study provided by a local foundry. It consisted of the production of a sand casting pattern in cast iron for a high pressure moulding machine. The investigation confirmed the feasibility of RCT for producing foundry tools. In addition it demonstrated the crucial role of casting simulation in the prevention of casting defects and the prediction of tool properties. The challenges of RCT were found to be exogenous mainly related to workmanship. An assessment of RCT manufacturing time and cost was conducted using the case study above mentioned as well as an additional one dealing with the manufacturing of an aluminium die for the production of lost wax patterns. Durations and prices of RCT steps were carefully recorded and aggregated. The results indicated that the AM of moulds was the rate determining and cost driving step of RCT if procurement of technology was considered to be a sunk cost. Overall RCT was found to be faster but more expensive than machining and investment casting. Modern surface analyses and scanning techniques were used to assess the quality of RCT tools in terms of surface finish and dimensional accuracy. The best surface finish obtained for the cast dies had Ra and Rz respectively equal to 3.23 μm and 11.38 μm. In terms of dimensional accuracy, 82% of cast die points coincided with die Computer Aided Design (CAD) data which is within the typical tolerances of sand cast products. The investigation also showed that mould coating contributed slightly to the improvement of the cast tool surface finish. Finally this study also found that the additive manufacturing of the sand mould was the chief factor responsible for the loss of dimensional accuracy. Because of the above, it was concluded that light machining will always be required to improve the surface finish and the dimensional accuracy of cast tools. Durability was the last characteristic of RCT tools to be assessed. This property was empirically inferred from the mechanical properties and metallographic analysis of castings. Merit of durability figures of 0.048 to 0.152 were obtained for the cast tools. It was found that tools obtained from Direct Croning (DC) moulds have merit of durability figures three times higher than the tools produced from Z-Cast moulds thus a better resistance to abrasion wear of the former tools compared to the latter.
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Calvert, Jacob Rollie. „Microstructure and Mechanical Properties of WE43 Alloy Produced Via Additive Friction Stir Technology“. Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/55816.
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In an effort to save weight, transportation and aerospace industries have increasing investigated magnesium alloys because of their high strength-to-weight ratio. Further efforts to save on material use and machining time have focused on the use of additive manufacturing. However, anisotropic properties can be caused by both the HCP structure of magnesium alloys as well as by layered effects left by typical additive manufacturing processes. Additive Friction Stir (AFS) is a relatively new additive manufacturing technology that yields wrought microstructure with isotropic properties. In this study, Additive Friction Stir (AFS) fabrication was used to fabricate WE43 magnesium alloy, with both atomized powder and rolled plate as filler material, into multilayered structures. It was found that the WE43 alloy made by AFS exhibited nearly isotropic tensile properties. With aging these properties exceeded the base material in the T5 condition. The toughness measured by Charpy impact testing also showed an increase over the base material. The relationships among tensile properties, Vickers microhardness, impact toughness, microstructure and thermal history are developed and discussed.Master of Science
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Brisenmark, Lucas, und Simon Lindström. „Image based analysis on powder spreadability in powder bed additive manufacturing“. Thesis, KTH, Materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-277895.
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Additive manufacturing is an increasingly popular industry that has gained significant traction in the last decade. Today there exists no way to predict how a powder will spread in a powder bed additive manufacturing machine or how well it will form into thin layers. This is important because major costs can be saved by using a test that predicts the spreading behaviour of powder. This ability to be spread will be given the name spreadability. To test the spreadability of powder, a machine that mimicked the pushing of the powder in powder bed additive manufacturing was used. Since there exist no metric for spreadability, the study decided to attempt to quantify the spreadability with the help of image analysis. In the image analysis the area of the powders was measured, and through a comparison of the area against a bounding geometry, a measurement for spreadability can theoretically be attained. To further validate the results and simultaneously search for possible correlations, the experimental data was compared against flowability data obtained from angle of repose and Hall flowmeter. The results showed that the method of choice worked well for measuring the area and gave data that could be used to interpret spreadability. The data also showed what seems to be a correlation with the flowability data. While no definitive conclusions could bedrawn due to a small sample size, the collected data does seem promising for future work.Additiv tillverkning är en alltmer populär industri som har fått stor uppmärksamhet under det senaste decenniet. Idag så finns det inga sätt som man kan förutse hur ett pulver kommer att bredas ut i en pulverbädds additiv tillverkningsmaskin eller hur bra den är på att bilda tunna lager. Detta är en viktig kunskap att förstå då stora kostnader kan sparas in genom att använda ett test som förutser utbredningsförmågan av pulver. Denna förmåga får namnet spridbarhet. För att kunna testa spridbarheten hos pulver, används en maskin som härmar puttandet av pulver i en pulverbädds additiv tillverkningsmaskin. Eftersom det inte finns någon metod att mäta spridbarhet med, så valde denna studie att försöka kvantifiera spridbarheten via en bildanalys. Med denna bildanalys kunde arean av pulver mätas och genom att jämföra denna mot en avgränsande geometri kan mätdata för spridbarheten teoretiskt fås fram.För att kunna validera resultatet, och samtidigt se om det finns en korrelation, jämfördes det med flytbarhetsdata från rasvinkelmätare och Hall flödesmätare. Resultaten visade att metoden klarade av att mäta arean, och gav resultat som kan användas för att tolka spridbarhet. Den data som framtogs visade också att det möjligtvis kan finnas en korrelation mellan spridbarhet och flytbarhet. Även om något klart svar inte kan ges på grund av en liten provstorlek, så verkar resultaten vara lovande för framtida arbeten.
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Yousaf, Daowd, und Kaveh javdanierfani. „Binder Jetting Additive Manufacturing Technology : The Effects of Build Orientation on The Printing Quality“. Thesis, Högskolan i Halmstad, Akademin för företagande, innovation och hållbarhet, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-45142.
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In recent years, multi-jet fusion technology became more popular as it has unlimited potential. Thanks to this technology, it became possible to produce products with complex geometries.This gives a massive advantage compared to the conventional manufacturing process, as by utilising 3D printers, the costs and environmental impact are reduced exponentially with regards to the fact that this is a new technology. Product quality is one of the most important factors when it comes to product manufacturing for a company to stay competitive in the market. This study was conducted in FABLAB at Halmstad University. The research focuses on different aspects of the fabricated test artefacts, such as surface roughness, tensile strength and dimensional deviation. How different printing parameters can affect the printing quality of the printed parts is then analysed. The result is then compared with designed CAD model. During this study, some experiments were conducted by printing test samples at different build orientations to define the printing quality. Measurement is conducted on the different test artefacts and quantified. The effect from build orientation on surface roughness, tensile strength and dimension accuracy were studied during this thesis. The test samples were measured by using appropriate measuring equipment that was available at Halmstad University. From the test results, it becomes clear that the build orientation directly impacts the printing quality of the printed test samples from the HP multi-jet fusion 3D printer
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Thimothi, Fredin, und Sreenivasan Sreejesh Chathengattil. „Cost Estimation of Additive Manufacturing : A case study of TylöHelo Company's Sauna Product“. Thesis, Högskolan i Halmstad, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-45504.
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The concept of Additive Manufacturing (AM) has been used extensively for a long time now, with many industries embracing it. In this modern lifestyle, peoples need to be different not only in their dressing styles but also to change their outlook on their living room interior, their homes, their gardening, and every aspect of their life. Thereby people need more customized products. So Additive manufacturing can provide mass customization to the needy ones. As a consequence, Additive manufacturing becomes more important, and industries realized this fact and they adopt it. However, one must know the cost associated with different Additive Manufacturing techniques and different parameters involved with Additive Manufacturing to reap the benefits of additive manufacturing technology. The ready-made sauna rooms of TylöHelo Company are the quickest and easiest to assemble of the many options, and this is used as a case study in this study. In this thesis, the cost analysis is performed on a TylöHelo sauna product – ‘Corner knot’ produced using two AM technologies such as SLA and FDM processes. The different parameters involved in the print settings were studied and it was optimized to get an optimal cost for these products. FDM printer Prusa MK3S and SLA printer form 2 and their respective slicing software were utilized for this purpose. From the results, it was found that FDM was a better alternative for producing the Corner Knot sample than the SLA process. It is because the cost associated with FDM and SLA is respectively 27.77 Kr and 55.33 Kr. Prusa printers were utilized for this purpose. The cost comparison between the solid-based AM technology Fused Deposition Modeling (FDM) and Liquid-based AM technology Stereolithography is conducted in this study and FDM is found to be the superior solution over SLA since the cost for the production FDM is lower than SLA. The orientation of knots and layer thickness are the different parameters associated with the build time of additive manufacturing. In the future, the cost comparison and parameters associated with other solid and liquid-based AM technology along with powdered-based AM technology can be conducted.
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Qi, Jianing, und Shilun Wei. „The Impact of Medical Devices Regulations on Notified Bodies and Additive Manufacturing“. Thesis, Uppsala universitet, Institutionen för samhällsbyggnad och industriell teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-414216.
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The medical device regulatory system, as well as the medical device market in the European Union (EU), is now facing challenges posed by the newest regulation, Medical device regulations (MDR). Researches have shown concerns and possible consequences related to this new regulation system from both the regulatory approval procedure and market development perspectives. This study aims to elaborate on a practical and objective situation of this latest shift and picture out a predictable scenario for the implementation of future technology like Additive Manufacturing (AM) in healthcare. These two objectives are addressed from the perspective of the core role in this system, Notified Bodies (NBs). Specifically, it answers the following questions: What is the impact of the MDR on the NBs’ operations? What is the impact of the MDR on the device building on AM from NBs’ perspective? A literature review is conducted on existing researches in the relevant fields mentioned in the research questions of this study. Then a self-completion questionnaire is generated and sent to NBs who offer the CE marking granting service for the medical devices around the EU. The eight responses for the survey indicate that the MDR influences NBs and the device building on AM from several perspectives. For the NBs, the number of NBs will decrease while the workload and new recruitment will increase. Also, the independence and competences of NBs will be improved by MDR. In the case of AM-relevant medical devices, MDR will pose specific issues on them while the market will be developed by ensuring the product quality and raising public awareness. These findings are valuable practical evidence to examine the application of MDR and the implementation of technology like AM in healthcare under MDR. Overall, it found that the MDR will cause a tough situation in the short term. At the same time, the far-reaching influence for the regulatory system, as well as the medical device market, is affirmative and expectable worthy.
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Doustmohammadi, Saeide. „Product Customization Through Digital Fabrication Technology“. The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1420635099.
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Oppon, Charles. „An investigation into the characteristics of polyurethane foam for medical applications produced using additive manufacturing technology“. Thesis, Northumbria University, 2016. http://nrl.northumbria.ac.uk/31612/.
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Polyurethane (PU) foam has unique characteristics making it suitable for many applications such as: aeronautics, automotive, building construction, marine, and many house-hold applications. PU’s biodegradability, biocompatibility, lightweight, and durability make it suitable for several medical applications. The porous structure of PU foams enables them to be used for lightweight components and for medical applications where the permeability allows nutrients to reach cell growth areas. The foam components are currently mainly manufactured by material removal i.e. subtractive machining or a casting/moulding processes. Additive Manufacturing (AM) processes (3D printing), build components in 2D layers and have been utilised to manufacture a range of products for many applications including: jewelry, footwear, industrial design, architecture, engineering and construction, etc. The additive processes have the ability to generate internal hollow structures or scaffolds. The nature of parts produced by AM technologies makes it fit for lightweight products such as aerospace parts, medical scaffolds, etc., in metals and polymers, however the technology has not been used to produce objects using PU as its material, due to the foaming nature of the material when its two base materials (polyol and Diisocyanate) encounter with each other. This research has undertaken a critical review of PU foaming processes, medical applications, and characteristics of AM technology processes. The effect of resins mixing ratios, temperature, and foaming direction on the physical and mechanical properties of PU foam have been investigated and used as a base to establish a platform for further development. The research has evaluated the suitability of Additive manufactured PU foam structures for further application such as medical scaffolds by comparing the foams produced using traditional method and have developed an AM production method (In-flight mixing system) for the material (PU). Based on the evaluations, a new technique has been pro-posed and tested which is able to generate PU 3D structures. Foam produced by the designed system has average pore size of 689μm which will allow the following: the flow of fluid such as blood, diffusion of waste products out of the scaffold, and cell infiltration and can therefore be suggested for the production of medi-cal scaffolds.
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Charles, Amal Prashanth, und Taylor Claudio Alexander Gonzalez. „Development of a Method to Repair Gas Turbine Blades using Electron Beam Melting Additive Manufacturing Technology“. Thesis, KTH, Industriell produktion, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-202367.
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This study focuses in using the electron beam melting additive manufacturing process to develop a framework to repair high performance gas turbine blades. These are currently fabricated using highly engineered super alloys, more specifically Inconel 738LC. The thesis focusses on the research on the current production methods of gas turbine blades, the operating environment inside the gas turbine, the most common failure modes as well as current methods of blade repair. This investigation includes studying the methods of production of metallic powders and the alloying effects of different elements in our required powder. A brief analysis was made to determine the economic viability for the usage of AM technology for mass production, and a proposition has been developed for the repair of turbine blades using additive manufacturing.
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Vaithilingam, Jayasheelan. „Additive manufacturing and surface functionalisation of Ti6Al4V components using self-assembled monolayers for biomedical applications“. Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/28474/.
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The ability to provide mass customised and biocompatible implants is increasingly important to improve the quality of life. Additive manufacturing (AM) techniques have obtained increasing popularity and selective laser melting (SLM), a metal-based AM technique with an ability to build complex and well defined porous structures, has been identified as a route to fabricate customised biomedical implants. Surface modification of an implant with a biomolecule is used to improve its biocompatibility and to reduce post-implant complications. In this thesis, the potential of a novel approach to use self-assembled monolayers to modify SLM fabricated surfaces with therapeutic drugs has been evaluated. Although there are numerous studies on the material development, process optimisation and mechanical testing of SLM fabricated parts, the surface chemistry of these parts is poorly understood. Initially, the surface chemistry of SLM as-fabricated (SLM-AF), SLM fabricated and mechanically polished (SLM-MP) and forged and mechanically polished (FGD-MP) parts made of Ti6Al4V was determined using an X-ray photoelectron spectrophotometer (XPS). Later the impact of laser power on the surface chemistry of the parts was also studied. A non-homogeneous surface chemistry was observed due to a change in the distribution of the alloying elements titanium, aluminium and vanadium on the surface oxide layer. Surface modification of the SLM fabricated component would be beneficial to obtain a homogenous surface chemistry, especially for biomedical application. Coating of self-assembled monolayers (SAMs) onto SLM fabricated Ti6Al4V structures was performed to modify their surface chemistry. 16-phosphanohexadecanoic acid monolayers (16-PhDA) were used to modify SLM-AF and SLM-MP surfaces. XPS and static water contact angle measurements confirmed the chemisorption of monolayers on these surfaces. The obtained results confirmed that SAMs were stable on the Ti6Al4V surface for over 28 days before its desorption. It was also witnessed that the stability of monolayers on the rough SLM-AF and smooth SLM-MP surfaces were not significantly different. Later, the 16-PhDA SAM coated Ti6Al4V SLM-MP surface was functionalised with a model drug, Paracetamol. An esterification reaction was performed to functionalise the phosphonic acid monolayers with Paracetamol. Surface characterisation revealed the sucessful attachment of Paracetamol to the SAMs. Bacterial infections from biomedical implants and surgical devices are reported to be a major problem in orthopaedic, dental and vascular surgery. Hence, to further explore the potential of the proposed method, Ciprofloxacin® a broad spectrum antibiotic was immobilised to the SAMs, previously adsorbed on the SLM-MP Ti6Al4V surfaces. Using the proposed approach, approximately 1.12 µg/cm2 of the drug was coated to the surface. Results showed that Ciprofloxacin® is highly stable under the oxidative conditions used in this study. Under in vitro condition, the drug was observed to release in a sustained manner. Antibacterial susceptibility tests revealed that the immobilised Ciprofloxacin® was therapeutically active upon its release. Thus, a novel methodology to fabricate customised and functionalised implants has been demonstrated for an improved biocompatibility and reduced post-implant complications.
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Brandemyr, Gabriella. „Powder bed additive manufacturing using waste products from LKAB's pelletization process : A pre-study“. Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-75421.
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This report is the result of a bachelor thesis project executed at Luleå University of Technology(LTU). The purpose of the project was to investigate the possibility to use the metal powder wasteproducts from LKAB’s pelletizing process for additive manufacturing as this would meaneconomic benefits for the sake of LKAB as well as environmental benefits.Two different powders were used in the experiments and were referred to as crush and dust. Theexperiments were made through the selective laser melting (SLM) method with varying laserparameters to observe their effect. These included the laser power and laser speed. Scanningelectron microscope (SEM), Energy Dispersive X-Ray Spectroscopy (EDS) and opticalmicroscopy were used for the analysis of the samples.The analysis of the chemical compositions showed that the powders were inhomogeneous anddiffered from each other. The crush powder contained phosphor and carbon which was lacking inthe dust and also had higher amounts of silicon and potassium. In spite of the inhomogeneouspowder and getting some agglomerations of half-melted grains on the tracks, the tracks tended tobe mostly homogenous. It was also observed that the tracks have a higher amount of carboncompared to the powder which probably derives from the substrate plate.The adherence of the tracks was greatest at a laser power between 200-300 W and a laser scanningspeed 0.5-1.75 m/min.The metal powder waste products from LKAB’s pelletization process could likely be used inadditive manufacturing, however, more work is needed in order to ensure the obtained results andcontinue with further experiments.
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Ingman, Richard. „ADAPTION OF A HEATSINK TO ADDITIVE MANUFACTURING. : INCLUDING A GUIDE TO INDUSTRIAL STARTUP OF AM“. Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-262655.
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This thesis is an investigation of the current status of additive manufacturing (AM) regarding different technologies, the level of implementation in industry and the future obstacles for further implementation. As a secondary objective, an existing heatsink for electronic equipment was redesigned, adapted to and improved using the design advantages of AM, and was later manufactured through 3D-printing in aluminium (AlSi10Mg). The thesis resulted in a summarized roadmap of recommended actions for Saab Surveillance in Järfälla in the near future. And a redesigned heatsink, which was tested to hold a static pressure of 30 bar, and simulated to achieve the same pressure drop in the channel and withstand the same vibration load as the old heatsink. At the same time, the new design reduced the total weight by 20% and increased the heat transferring surface area of the channel by 100%, potentially doubling the heat transfer capability.Detta examensarbete har undersökt den nuvarande statusen hos additiv tillverkning (AM) vad gäller olika teknologier, hur långt implementeringen i industrin kommit och framtida hinder som måste lösas för vidare implementering. Som sekundärt mål för projektet har en existerande elektronikkylare designats om och förbättrats med hjälp av designfördelarna hos AM, och tillverkades sedan genom 3D-printning i aluminium (AlSi10Mg). Arbetet har resulterat i en sammanfattad ’roadmap’ med rekommendationer för vad Saab Surveillance i Järfälla bör göra inom AM den närmaste tiden, samt en ny kylare som framgångsrikt trycktestades upp till 30 bar. Genom simuleringar visades den uppnå samma tryckfall och klara samma vibrationer som den tidigare kylaren, samtidigt som den väger 20% mindre och har en 100% ökning av kylkanalens våta area vilket potentiellt innebär en dubblering av kylförmågan.
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Li, Jiaqi. „Study of Nano-Transfer Technology for Additive Nanomanufacturing and Surface Enhanced Raman Scattering“. University of Dayton / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1628006052402601.
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Roca, Jaime Bonnín. „Leaders and Followers: Challenges and Opportunities in the Adoption of Metal Additive Manufacturing Technologies“. Research Showcase @ CMU, 2017. http://repository.cmu.edu/dissertations/1092.
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Policymakers in the United States and elsewhere have recognized that a broad and competitive manufacturing sector is crucial to a robust economy and that to remain competitive, a nation must invent and master new ways of making things. Moving technologies from laboratory to commercial success poses considerable challenges however. If the technology is radically new, this transition can be so risky and investment-heavy that only very large private firms can attempt it. One such new technology is metal additive manufacturing (MAM). MAM provides a vivid illustration of the tensions policymakers must resolve in simultaneously supporting the commercialization of early-stage innovations of strategic national interest, while fulfilling the government’s duty to ensure human health and safety. After an initial chapter with a general overview of additive manufacturing technologies, this dissertation explores these tensions from the perspective of two very different industrial contexts: the U.S. as a technology leader and trailblazer in the development of the technology, and Portugal as a technology follower with severely constrained resources. In the first case study, I use the extreme case of MAM (an emerging technology with many sources of process uncertainty) in commercial aviation (an industry where lapses in safety can have catastrophic consequences) to unpack how the characteristics of a technology may influence the options for regulatory intervention. Although my work focuses on the U.S. and the Federal Aviation Administration’s regulation, I expect this work to have an international scope, given that in most countries regulation is heavily influenced by, if not an exact copy of, the U.S. regulation. Based on my findings, I propose an adaptive regulatory framework in which standards are periodically revised and in which different groups of companies are regulated differently as a function of their technological capabilities. I conclude by proposing a generalizable framework for regulating emerging process-based technologies in safety-critical industries in which the optimal regulatory configuration depends on the industry structure (number of firms), the performance and safety requirements, and the sources of technological uncertainty. In the second case study, I analyze the adoption of polymer (PAM) and metal (MAM) additive manufacturing technologies in the Portuguese molds industry, both of which offer important benefits to their products. Leveraging archival data (related to the history of Portuguese institutions, and the development of additive manufacturing both globally and in Portugal), insights from 45 interviews across academia, industry, and government; and 75 hours of participant observations, we develop insights about why institutional instability affected the adoption of Polymer Additive Manufacturing (PAM) and Metal Additive Manufacturing (MAM) differently. In both cases, Portugal invested in the technology relatively early, and in the case of PAM the research community has been able to move towards high-tech applications. In contrast, the adoption of MAM has been modest despite its potential to greatly improve the performance and competitiveness of metal molds. From the comparison between PAM and MAM, we generate theory about which technological and contextual factors affect their ‘technological forgiveness’, defined as the resiliency of a new technology’s adoption to institutional instability. We conclude by proposing a generalizable framework for ‘forgiveness’ in different industrial contexts. The final chapter of this dissertation contains practical recommendations for regulators and managers interested in adopting the technology. Policymakers in the aviation industry may want to encourage the creation of programs to gather more flight experience with MAM parts. Small aircraft and other applications with higher risk tolerance than commercial aviation might represent more important channels to gather information, as the history of composite materials suggests. More importantly, regulators may need to introduce clauses in their rules to regulate MAM to avoid situations of ‘regulatory lock-in’ which could harm the long-term potential of the technology. Despite the potential of additive manufacturing, we believe that near-term expectations for it are overblown. In general, additive manufacturing holds great promise, but in many areas the cart has gotten ahead of the horse. Much of the technology is still under development. The history of comparable technologies such as composite materials and high-performance castings shows that the problems may take decades to resolve. For now, additive manufacturing is cost-competitive only in niche applications — for instance, those involving plastics. Businesses that want to plunge into additive manufacturing should be cognizant of the challenges. Determining whether it makes sense to invest in additive manufacturing will require experimentation and learning.
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Hofacker, Eva. „QUALITY IMPROVEMENT OF CERAMIC PARTS FORMEDICAL APPLICATIONS THROUGHOPTIMIZATION OF THE ADDITIVE MANUFACTURING ANDPOST-PROCESSING PROCESSES“. Thesis, KTH, Industriell produktion, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-226170.
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Additive Manufacturing (AM) is beneficial for medical applications in which tissues must be replaced because AM enables the fabrication of highly complex three-dimensional structures. In this study the AM and the post-processing steps of additive manufactured ceramic parts of a specific material for tissue replacement were examined in order to optimize the parts’ quality. Visual inspection and microscopic techniques, weighing, dimensional measurements, and flexural bending tests were used for the result evaluation. Different cleaning agents and methods were tested with the result that the current cleaning agent and method had the best cleaning performance. With changed orientation on the building platform, changed supports during the AM and defined positions in the furnace during sintering, the parts’ quality was clearly improved, i.e. the parts had no longer countless cracks, were not warped anymore and had a smooth surface. Post-curing with UV light was found to have a detrimental impact on the parts’ quality. Tests with different sintering temperatures showed, that the sintering temperature influences the appearance, the degree of shrinkage, the degree of fusion, and the flexural strength of the parts. Hence, depending on the intended application the sintering parameters must be specified for each part.Additiv tillverkning är fördelaktigt för medicinska tillämpningar där vävnader måste bytas ut eftersom additiv tillverkning möjliggör tillverkning av högkomplexa tredimensionella strukturer. I denna studie undersöktes additiv tillverkning och efterbehandlingsstegen av tillsatsframställda keramiska delar av ett specifikt material för vävnadsersättning för att optimera delarnas kvalitet. Visuell inspektion och mikroskopiska tekniker, vägning, dimensionella mätningar och böjningsböjningstest användes för resultatutvärderingen. Olika rengöringsmedel och metoder testades med det resultat att det aktuella rengöringsmedlet och metoden hade den bästa rengöringsytan. Med ändrad orientering på byggplattformen och ändrade stöd under additiv tillverkning och definierade positioner i ugnen under sintring förbättrades delarnas kvalitet klart, dvs delarna hade inte längre otaliga sprickor, inte varvade längre och hade en jämn yta. Efterhärdning med UV-ljus har visat sig ha en negativ inverkan på delarnas kvalitet. Test med olika sintringstemperaturer visade att sintringstemperaturen påverkar utseendet, graden av krympning, graden av fusion och böjhållfastheten hos delarna. Därför, beroende på den avsedda tillämpningen, måste sintringsparametrarna anges.
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Ekman, Marcus. „Design Study of a Wing Rudder : Exploring the Possibility to Implement Additive Manufacturing“. Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-64522.
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Subtractive manufacturing are the most common methods in the aerospace industry to manufacture components. In these parts the buy to fly ratio is low and it needs accurate strengths analyses to static and dynamic loads especially were the different parts relate to each other with fasteners in the assembly work. Additive manufacturing has now been developed to be of such quality that the aerospace industry see the potential to use the technology in their production of parts. It has been possible to make them lighter, stronger and reduce the total amount of parts in an assembly. This mean probably some changes to the stakeholders in the process of their product development. Engineers who are working on the products will need to face the design aspects and restrictions with AM to choose the right component/sub-assemblies to convert to AM parts. This thesis will address the possibility to redesign a wing rudder and to get some knowledge about the engineer’s point of view of AM and how it may affect them. Today there are several aerospace industries adopting AM and get airworthy components to less critical parts as brackets but also parts in the engines as the fuel nozzle in an Airbus (Trimble, 2016). For larger parts, there have also been studies to use AM for example internal galley partition but the result is it will take too long time to print by todays machines. There are several different methods for AM and Powder Bed System is popular in the aerospace industry according to its geometrical correctness to the CAD model (Dordlofva, Lindwall, & Törlind, 2016). Commercial aircrafts industry starts to get harder regulations for their emissions to get lighter planes and less air resistance. AM open up the possibilities to meet these requirements by producing parts which was impossible to produce before. The design process for AM design today are not fully known yet, which leave a lot to imagination. There are general design rules on how to design for AM build but it does not necessary mean the part will be correctly built. There are several cost driven aspects with AM, the most expensive part is the print time but there are different aspects to. For example, CNC machining may be needed after the AM build and add cost for subtractive manufacturing. Interviews with engineer’s groups have been made to conduct their thoughts and knowledge of AM and how it may affect their work. Some uncertainties were mentioned and it was most focused on the process and the reliability of the finished part. The engineers think the design process will be almost the same and only change boundary conditions. To get ideas, a workshop was made with some design guidelines for development of different designs on the wing rudder and to bring positive and negative aspects to the design. An overall cost calculation was made for a few parts and the result shows that it is hard to compete with the design of the wing rudder today. The most important aspects for a success of AM is the print speed, qualified manufacturing processes and CAD software support for the engineers.Flygindustrin använder sig främst av subtraktiv bearbetning i sin framställning av de olika komponenterna till ett flygplan. Det blir då ofta en väldigt låg grad av materialutnyttjande, endast några procent återstår av det inköpta utgångsmaterialet. Till det tillkommer monteringsarbete och noggranna hållfasthetsanalyser, både statisk och utmatningshållfasthet av sammanbyggda skarvar där fästelement är en del. Den additiva tillverkningen har nu utvecklats och visat sig inneha kvalitéer för att klara kraven som ställs i flygindustrin. Det kan göra detaljerna lättare, starkare och minska antalet komponenter i monteringsarbetet. Det kan innebära en hel del förändringar för olika intressenter som får börja tänka annorlunda. Ingenjörer som arbetar med produktframtagning kommer att ställas inför utmaningen att applicera denna teknik på lämpliga delar/delkonstruktioner. Detta examensarbetet undersöker möjligheten att designa ett vingroder till ett flygplan och bilda en uppfattning om ingenjörernas förtroende för additiv tillverkning samt hur det kommer påverka dem. Det finns idag flera flygindustrier som har påbörjat att ta fram flygvärdiga komponenter, framförallt mindre kritiska fästelement men även en del artiklar i motorer så som bränslemunstycke hos Airbus (Trimble, 2016). De har analyserat möjligheten att använda additiv tillverkning på större artiklar såsom inre kabinstruktur men har kommit fram till att det tar för lång tid att tillverka med dagens maskiner. Det finns flertalet olika additiva tillverkningsmetoder men den som står ut är pulverbäddskrivaren då den har en bättre geometrisk korrekthet gentemot CAD modellen (Dordlofva, Lindwall, & Törlind, 2016). Nya reglementen för utsläpp i den komersiella flygindustrin pressar företagen att bygga bättre flygplan som är lättare och därmed får mindre luftmotstånd. Designprocessen för additiv tillverkning är inte given då det inte finns några givna processer som täcker hela processen. Det finns generella design-riktlinjer i vad de olika maskinerna klarar av att bygga, men samtidigt är det ingen garanti att genom att följa dessa riktlinjer skapa en fungerande design. Det finns flera olika kostnadsdrivande aspekter med additiv tillverkning. Det som mest driver kostnaden idag är den låga skrivarhastigheten. Andra kosnadsdrivare är om det tillkommer efterarbete för att uppfylla toleranser eller få en korrekt / plan sammanfogningsyta. Arbetet har utförts med intervjuer av ingenjörsgrupper för att skapa en uppfatting om deras syn på additiv tillverkning och hur det skulle ändra deras arbete. En viss osäkerhet förekom men det berodde framförallt på osäkerheten för säkring av processen, dvs tillverkningsprocessen och att kunna vara säker på att detaljen håller måttet. De ansåg att designprocessen inte skulle förändras så mycket, utan bara att randvillkoren skulle ändras. Utifrån workshops och designriktlinjer har koncept tagits fram och utvärderats med för och nackdelar. En översiktlig kostnadskalkyl har gjorts som visar på att det blir svårt att designa roder som en större enhet för additiv tillvekning som är ekonomiskt jämförbart med dagens tillverkingsmetoder. De viktigaste framgångsfaktorerna för additiv tillverkning är ökad skrivarhastighet, kvalificering av tillverkningsprocesserna och CAD stöd för ingenjörerna.
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MARTINELLI, ELISA MARTINA. „CUSTOMER DRIVEN SUPPLY CHAINS AND DIRECT DIGITAL MANUFACTURING TECHNOLOGY“. Doctoral thesis, Università Cattolica del Sacro Cuore, 2018. http://hdl.handle.net/10280/39859.
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Nel contesto della nuova rivoluzione industriale, alti livelli di turbolenza, dinamismo, volatilità, globalizzazione, competizione e un diverso ruolo del consumatore riconfigurano il panorama delle supply chain e delle innovazioni. Nonostante il valore co-creato e le ultime innovazioni in ottica customer driven siano ormai elementi imprescindibili, poche ricerche si sono focalizzate sulle caratteristiche di una supply chain guidata dal consumatore e sull’impatto o implementazione della stampa 3D. Pertanto, questa tesi mira ad esplorare gli aspetti principali della customer driven supply chain e della direct digital manufacturing technology. Il Paper I presenta una revisione sistematica della letteratura e fornisce un quadro concettuale utile per organizzare i contributi più recenti sull'argomento, implementando la teoria e suggerendo linee guida per i manager. Il Paper II e Paper III propongono ricerche qualitative mediante singoli casi studio che rispettivamente analizzano come la stampa 3D è in grado di facilitare la supply chain customer centricity attraverso la co-creazione di valore nel settore aerospaziale e come un technology provider può implementare un’innovazione customer centric nel settore della gioielleria italiana. Gli studi suggeriscono modelli concettuali e proposizioni che incrementano la letteratura esistente e guidano i manager.
Questa tesi contribuisce all'esplorazione dei recenti progressi in merito all’'orientamento della supply chain e della direct digital manufacturing technology fornendo analisi critiche approfondite relative a diverse metodologie.In the new industrial revolution, high levels of turbulence, dynamism, volatility, globalization, competition and modified customer’s role reconfigure supply chains and innovations landscape. Even if value co-creation and last technologies towards customer driven orientation are unavoidable elements, few contributions have focused on customer driven supply chain characteristics and on 3D printing impact on supply chain or elements of its implementation. For this reason, the thesis aims to explore the main features of customer driven supply chains and direct digital manufacturing technology. Paper I presents a systematic literature review that shows a conceptual framework able to organize the most recent contributions on the topic, implementing the knowledge on the theme and suggesting guidelines to managers. Paper II and Paper III provide qualitative constructive single case study research respectively focused on how 3D printing can enable supply chain customer centricity by value co-creation in the aerospace sector and how 3D printing can be implemented by a technology provider in the Italian jewellery sector. The studies suggest conceptual framework and propositions for improving existing knowledge and addressing managers. This thesis contributes to the exploration of recent advancements in supply chain orientation and direct digital manufacturing technology by providing deep critical analysis related to diverse methodologies.
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Zhu, Xiaobao. „Consensus-Oriented Cloud Additive Manufacturing Based on Blockchain Technology: An Exploratory Study on System Operation Efficiency and Security“. University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1592171839143159.
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Lindwall, Angelica. „Additive Manufacturing in Product Design for Space Applications : Opportunities and Challenges for Design Engineers“. Licentiate thesis, Luleå tekniska universitet, Människa och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-68216.
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Svensson, Marcus. „Selection of a product component for topology optimization and additive manufacturing“. Thesis, Jönköping University, JTH, Industriell produktutveckling, produktion och design, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-52791.
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This is a master thesis research on how to select the right components in a product, considering reducing the weight with topology optimization (TO) and adaption for additive manufacturing (AM). It is well established that manufacturing of complex structures can be achieved with AM, the possibility of integrating assembled components and improve features will therefore be investigated. The new component structure must still withstand the loads that it is subjected to during usage, to not permanently deform or break. In this research the studied product was a handheld Husqvarna chainsaw. Initially a feasibility study was conducted, where the product was disassembled and physically investigated for potential component cases. Additional knowledge was gathered with one semi structured interview per case, with experienced design engineers. Followed by one semi structured interview with AM experts, regarding available AM technique and similar material. Selection of case to continue with was based on the interviews information and Pughs decision matrix, with weighted criterions. TO were used for finding the optimal material distribution. The new component design was analyzed with linear finite element analysis to fulfill both the component and material stress requirements. Component orientation and support structure for AM was analyzed with computer aided engineering software. This resulted with integrating thirteen components for the engines cylinder into one component. The new design resulted in a weight reduction of 31%, while utilizing only 57% of the allowed stress limit. Also, the first 23 natural frequencies were improved with a new type of cooling fin structure, with an increased area of 15%. These results encourage the thesis workflow methodology usage for other products. In conclusion the established workflow of methods resulted in selecting a suitable case for integrating components with feature improvement and adaption of the new design with TO for AM, to reduce the weight.
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Vayre, Benjamin. „Conception pour la fabrication additive, application à la technologie EBM“. Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENI096/document.
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Les procédés de fabrication additive sont aujourd'hui de plus en plus utilisés dans l'industrie. Parmi les différentes technologies existantes, les procédés additifs métalliques, et notamment les procédés en couches, sont les plus prometteurs pour la conception de produits mécaniques. Des travaux ont été menés sur la thématique de la conception de produits réalisés par ces moyens, il traitent principalement du choix du procédé le plus adapté, de l'optimisation de formes ou présentent des cas de reconception. Il n'existe cependant pas de démarche globale de conception de produits qui permettent de prendre en compte les spécificités des procédés additifs en couches, notamment leurs contraintes de fabrication.Lors de ce travail de thèse, les changements que ces procédés introduisent dans le domaine des possibles en conception de produits ont été montrés et illustrés par des pièces réalisées par EBM. De nouvelles opportunités s'offrent au concepteur, comme l'accès à l'ensemble du volume de fabrication, la facilité de réalisation de pièces complexes, la possibilité de réaliser des treillis tridimensionnels et la capacité de produire des mécanismes sans assemblage. Les contraintes de fabrication de ces procédés sont spécifiques. Les phénomènes thermiques lors de la fabrication ont une incidence sur la fabricabilité et la qualité des pièces. La phase de retrait de poudre impose quant à elle des contraintes d'accessibilités. Pour prendre en compte cette évolution, il est nécessaire de concevoir spécifiquement les pièces pour la fabrication additive.Le procédé EBM est au centre du travail réalisé. Il s'agit d'un moyen de fabrication additive en couches, par fusion, à l'aide faisceau d'électrons. Les phénomènes thermiques, qui peuvent causer déformations et mauvaise intégrité de la matière, l'opération de dépoudrage et la problématique de la qualité des pièces fabriquées par EBM ont fait l'objet de caractérisations expérimentales. La durée de fabrication et le coût de revient technique des pièces réalisées par EBM ont également été étudiés, afin d'établir la relation entre durée, coût et géométrie des pièces.Pour de prendre en compte les contraintes explicitées auparavant, et pour bénéficier des importantes libertés que ce procédé offre aux concepteurs, une démarche de conception a été proposée. Cette démarche consiste à générer une ou plusieurs géométries initiales, soit directement par le concepteur, soit par l'utilisation d'outils d'optimisation topologique, à partir de données extraites du cahier des charges. Une fois le balançage de la pièce choisi (en prenant en compte les contraintes de fabrication, le tolérancement de la pièce et la productivité de la fabrication), la pièce est modélisée en incluant un jeu de paramètres pour effectuer une optimisation paramétrique. Cette optimisation permet de dimensionner la pièce, tout en prenant en compte les contraintes de fabrication. A l'issue de cette phase d'optimisation, la géométrie finale est obtenue en prenant en compte les exigences des opérations de parachèvement éventuelles et en définissant les supports, s'ils sont nécessaires. Cette démarche a été illustrée par la reconception de deux pièces mécaniques qui répondent aux exigences de leur cahier des charges fonctionnel, sont fabricables à l'aide du procédé EBM et offrent des gains de masse importants.Enfin, un chapitre particulier est consacré aux perspectives mises en évidence (et ayant parfois fait l'objet de travaux préliminaires) à l'occasion de ce travail de thèseNowadays, the use of Additive Manufacturing processes keeps growing in the industry. Among the numerous kinds of AM processes, metallic additive manufacturing processes, and metallic Additive Layer Manufacturing in particular, are the most interesting from a mechanical designer point of view. Several research studies have been conducted on the topic of Design For Additive Manufacturing, mostly discussing the choice of AM processes or presenting the redesign of parts. There is no specific design methodology for ALM processes that takes their specificities into account.During this PhD thesis, the changes that ALM processes bring to the design space were investigated. The designer has the opportunity to easily manufacture thin parts, complex parts, lattice structures or mechanisms that don't need any assembly. These processes also have specific manufacturing constraints compared to conventional processes. The heat dissipation is the most important factor since it can cause distortions and porosities. Powder removal, surface and geometrical quality also need to be considered during design. A specific design for additive manufacturing methodology is necessary to take these changes into account.This work focuses on the Electron Beam Manufacturing process. Experiments were conducted and analyzed to assess the manufacturability regarding the thermal phenomena (during melting), the powder removal and the quality of the parts produced by EBM. The impact of the part geometry on manufacturing duration and manufacturing cost was also established.In order to use allow designers to use these pieces of information, we suggested a designing methodology. From the requirements of the parts, one or several parts are generated by the designer or by using topological optimization tools. The orientation of the part inside the manufacturing space is set before designing a refined parametric geometry. This parametric geometry is optimized in order to meet the user requirements as well as the EBM requirements. The last step is the modification of the geometry to comply with the finishing operations (machining allowances for example) and the placement of supports, if needed. This methodology was illustrated with the redesign of two example parts and showed important mass savings from the parts (while meeting user and process requirements).The prospects discovered and highlighted during this work, some of which were preliminary investigated, are presented in a specific chapter
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Faresani, Mahdi Amirian, und Rosa Hadipoor. „Additiv Tillverkning i Fordonsindustrin : Avgörande faktorer vid val av lämplig 3D-skrivarteknik Additive Manufacturing in Automotive Industries - Decisive factors in the selection of suitable 3D printing technology“. Thesis, Högskolan i Borås, Institutionen Ingenjörshögskolan, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-17975.
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Additiv tillverkning (AT) eller 3D-utskrivning är en teknologi som har berömts den senaste tiden och förutsägs kommer att förändra hela tillverkningsindustrin. Dessa termer hänvisar båda till ett antal tillverkningstekniker där ett objekt framställs skikt för skikt genom att successivt tillföra material i tunna lager.Baserat på en litteraturstudie och intervjuer med experter inom området undersöker denna studie möjligheten att använda AT inom företaget CJ Automotive (CJA) vilket är en underleverantör inom fordonsindustrin som tillverkar olika slags pedalsystem. Rapporten beskriver additiv tillverkning, dess fördelar och olika användningsområden. Olika AT-tekniker, AT-material och välkända 3D-skrivartillverkare presenteras. Signifikanta fakta rörande både kvalitet, kostnad och teknik redogörs för. Även en jämförelse mellan olika tekniker redovisas.Denna rapport innehåller riktlinjer för hur ett företag ska tänka och vilka faktorer som är viktiga vid val av rätt 3D-skrivarteknik. Studien pekar på att det finns många fördelar med att utnyttja 3D-skrivare under utvecklingsprocessen på företaget. Detta kommer att påskynda utvecklingsprocessen och eventuellt förbättra produkterna till följd av mer flexibilitet och designmöjligheter. Slutligen föreslås två AT-tekniker som tycks vara de lämpligaste med tanke på företagets verksamhet.Program: Högskoleingenjörsexamen i Maskiningenjörprogrammet - Produktutveckling
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Graf, Marcel, Andre Hälsig, Kevin Höfer, Birgit Awiszus und Peter Mayr. „Thermo-Mechanical Modelling of Wire-Arc Additive Manufacturing (WAAM) of Semi-Finished Products“. MDPI AG, 2018. https://monarch.qucosa.de/id/qucosa%3A33161.
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Additive manufacturing processes have been investigated for some years, and are commonly used industrially in the field of plastics for small- and medium-sized series. The use of metallic deposition material has been intensively studied on the laboratory scale, but the numerical prediction is not yet state of the art. This paper examines numerical approaches for predicting temperature fields, distortions, and mechanical properties using the Finite Element (FE) software MSC Marc. For process mapping, the filler materials G4Si1 (1.5130) for steel, and AZ31 for magnesium, were first characterized in terms of thermo-physical and thermo-mechanical properties with process-relevant cast microstructure. These material parameters are necessary for a detailed thermo-mechanical coupled Finite Element Method (FEM). The focus of the investigations was on the numerical analysis of the influence of the wire feed (2.5–5.0 m/min) and the weld path orientation (unidirectional or continuous) on the temperature evolution for multi-layered walls of miscellaneous materials. For the calibration of the numerical model, the real welding experiments were carried out using the gas-metal arc-welding process—cold metal transfer (CMT) technology. A uniform wall geometry can be produced with a continuous welding path, because a more homogeneous temperature distribution results.
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Yang, Hong, und Dan Luo. „A Study of Additive Manufacturing Technology’s Development and Impact Through the Multi-Level Perspective Framework and the Case of Adidas“. Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254254.
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The Additive Manufacturing (AM) technology, known as 3D printing, is regarded as the ‘next generation of manufacturing’. It is classified as a disruptive technology and AM has attracted scholars worldwide and received extensive attention in various industries, which is significantly changing the way we design, produce, distribute and consume. This paper reviews how the AM development can be explained as a process of technological transition from a radical technological innovation to a social level technology, through integrating the technological innovation and the multilevel perspective (MLP) theories. In this way, we present a conceptual framework that provides a foundation for discussing AM trajectory and discover a development prediction of AM technology in the lens of MLP theoretical perspective. Secondly, the paper elaborates how AM is impacting businesses within the scope of open innovation through a case study on Adidas, to provide empirical support for similar industrial players to better predict the innovation trajectory through AM applications.
41
Barsing, Jonas. „A Cost Breakdown and Production Uncertainty Analysis of Additive Manufacturing : A Study of Low-Volume Components Produced with Selective Laser Melting“. Thesis, Blekinge Tekniska Högskola, Institutionen för industriell ekonomi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-16730.
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Background: Additive manufacturing has recently gained cogency as a final part manufacturing technique. The method uses a layer-upon-layer technique to build three-dimensional objects. This technique has many advantages creating new opportunities regarding production. Purpose: The purpose of the study is to investigate cost elements, cost drivers, their weight distribution, and to explore production uncertainties of the additive manufacturing process. The production uncertainty parameters of the explored uncertainties are then evaluated to investigate how some of them impacts the production cost of the case component. Method: The following study have used qualitative data collection methods in terms of interviews together with a pre-study and a sensitivity analysis tool to identify cost impacts of uncertainty parameters. Five primary interviews were performed with employees at the company with relevant knowledge of the studied field. Results: The result shows that the product cost can be divided into two categories of material cost and manufacturing costs, these two categories then have different cost elements that drives cost. The explored uncertainties of the process consist of both aleatory and epistemic uncertainty. The explored production uncertainty parameter that affects the final product cost the most is the time needed to finish the AM build. Conclusions: Considering production uncertainty is important in order to have reliable and accurate cost estimations. The three explored production uncertainties that have the most significant impact on the final product cost is the yearly machine running time, the SLM machine time needed to finish the component, and reduced manning time in the operations. These three uncertainty parameters should, therefore, have a larger focus than variables that do not have the same impact on the final product cost, to create better cost estimations.Bakgrund: Additiv tillverkning har på senaste tiden fått slagkraft som en produktionsteknik för slutprodukter. Additiv tillverkning använder en lager på lager teknik för att bygga tre-dimensionella objekt. Denna teknik har många fördelar som skapar många nya produktionsmöjligheter. Syfte: Syftet med studien är att undersöka kostnadselement, kostnadsdrivare, fördelningen av kostnader och att utforska produktionsosäkerheter inom additiv tillverkning. De utforskade osäkerhetsparametrarna inom processen är sedan studerade för att se hur de påverkar den slutgiltiga produktkostnaden. Metod: Följande studie har använt kvalitativa datainsamlingsmetoder i form av intervjuer tillsammans med en förstudie och ett utvecklat känslighetsanalysverktyg för att identifiera kostnadsförändringar på grund av förändringar i osäkerhetsparametrar. Fem stycken intervjuer har genomförts med anställda på företaget som har relevant kunskap inom området. Resultat: Resultatet visar att produktkostnaden kan delas upp i två kategorier, materialkostnad och tillverkningskostnad. Dessa två kategorier består sedan av olika kostnadselement som driver kostnader. De utforskade produktions osäkerheterna inom processen består av två typer av osäkerheter beskriven i teorin. Den produktionsosäkerhetsparameter som har störst påverkan på produktens slutkostnad är SLM maskintiden som krävs för att bygga komponenten. Slutsatser: Att beakta produktionsosäkerheter i kostnadsuppskattningar är viktigt för att uppskattningarna ska vara tillförlitliga och korrekta. De tre studerade produktionsosäkerheterna som har störst påverkan på den slutgiltiga produktionskostnaden är årlig maskinanvändning, SLM maskintiden som krävs för att bygga komponenten och bemanningstiden för operationerna. Dessa tre osäkerhetsparametrar bör därför ha ett större fokus eftersom de har störts påverkan på slutresultatet.
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Craft, Garrett Michael. „Characterization of Nylon-12 in a Novel Additive Manufacturing Technology, and the Rheological and Spectroscopic Analysis of PEG-Starch Matrix Interactions“. Scholar Commons, 2018. http://scholarcommons.usf.edu/etd/7137.
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In this work differential scanning calorimetry, dynamic mechanical analysis, Fourier-Transformed Infrared Spectroscopy [FT-IR] and polarized light microscopy will be employed to characterize polymeric systems. The first chapter broadly covers polymer synthesis and important characterization methods.
In the second chapter, a polyamide (PA12) will be sintered via a novel additive manufacturing (AM) technology developed here at USF termed LAPS (Large Area Projection Sintering). LAPS uses extended sintering timespans to ensure complete melting and densification of the polymer powder over the entire two-dimensional area of the part’s footprint. Further, it allows for the printed layer to crystallize and shrink in its entirety as the temperature falls below the crystallization temperature prior to the next layer being added. The printed parts (termed coupons) will be assayed by DSC and polarized light microscopy to determine sintering efficacy. Additionally, the parts will be compared to coupons printed with conventional methods to show that the USF AM technology shows superior elongation at break (EaB), with comparable ultimate tensile strength (UTS) and Young’s Modulus to laser sintered coupons. This is notable as conventional AM methods produce parts which usually compromise between EaB and modulus. The EaB of LAPS-printed parts is comparable to injection molding (IM) grade PA12, which is remarkable as IM grade PA12 powder normally has higher molecular weight and limited crystallinity. The reduced crystallinity of IM grade PA12 parts is thought to be due to the high shear rates during injection and fast cooling rates post-fabrication. Further, the USF LAPS parts show minimal or no detectable porosity. Porosity is an artifact of the sintering process which conventional techniques like laser sintering (LS) have little ability to mitigate, as higher energy wattages simply burn and degrade the polymer surface with insufficient time available for heat transfer and bulk melt flow. Porosity is documented as one of the leading causes of part failure and decreased mechanical properties in the literature, and as such the USF AM technology is in the process of being patented as of March, 2018.
Chapters three through six will explore a phenomenon first noticed by clinicians at the James A. Haley Veterans Hospital. They observed that starch-thickened drinks for patients suffering from dysphagia became dangerously thinned down upon addition of the osmotic drug polyethylene glycol (PEG) 3350, marketed as Miralax®. Starch-based hydrocolloids are common thickeners used for patients with dysphagia, and so any incompatibility with such a ubiquitous drug as PEG 3350 poses an immediate danger. Patients with the disorder can suffer increased rates of aspiration-related pneumonia, incurring up to nearly a 60% fatality rate within a year. Chances for aspiration greatly increase for food items which are too inviscid to safely swallow. Rheology and FT-IR spectroscopy will be used to show that the breakdown of the starch network in aqueous solution is dependent upon the molecular weight of PEG. As the molecular weight of PEG is reduced to that of a small molecule (~300MW) from its large drug form (3350MW), the structure stabilizes and can resist shearing forces in a steady shear rheological experiment. Spectroscopy will show that PEG molecular weight also influences syneresis and the crystallinity of the starch hydrocolloid solutions.
It is postulated that the molecular weight of PEG influences its miscibility in starch solutions, and its ability to interrupt the hydrogen bonding and entanglements which maintain the elastic framework which allow starch thickeners to impart viscosity and resist shearing forces. When this framework collapses, absorbed water is expelled as evidenced as a biphasic separation where water collects on top of the starch suspension. This was the phenomenon observed by the clinicians at the Veterans’ Hospital.
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Kumar, Kotha Vinod. „Subtractive and additive manufacturing technology in moulding industry“. Master's thesis, 2016. http://hdl.handle.net/10400.8/2148.
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This report is a review of additive and subtractive manufacturing
techniques. This approach (additive manufacturing) has resided
largely in the prototyping realm, where the methods of producing
complex freeform solid objects directly from a computer model
without part-specific tooling or knowledge. But these technologies are
evolving steadily and are beginning to encompass related systems of
material addition, subtraction, assembly, and insertion of components
made by other processes. Furthermore, these various additive
processes are starting to evolve into rapid manufacturing techniques
for mass-customized products, away from narrowly defined rapid
prototyping. Taking this idea far enough down the line, and several
years hence, a radical restructuring of manufacturing could take place.
Manufacturing itself would move from a resource base to a
knowledge base and from mass production of single use products to
mass customized, high value, life cycle products, majority of research
and development was focused on advanced development of existing
technologies by improving processing performance, materials,
modelling and simulation tools, and design tools to enable the
transition from prototyping to manufacturing of end use parts.
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Costa, José Manuel Monteiro. „METAL-BASED ADDITIVE MANUFACTURING: Evaluation of metallic parts produced with Additive Manufacturing Technology at YAZAKI Europe Limited“. Dissertação, 2016. https://hdl.handle.net/10216/87466.
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45
Costa, José Manuel Monteiro. „METAL-BASED ADDITIVE MANUFACTURING: Evaluation of metallic parts produced with Additive Manufacturing Technology at YAZAKI Europe Limited“. Master's thesis, 2016. https://hdl.handle.net/10216/87466.
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46
WU, CHIH-HAN, und 吳治翰. „DLP Additive Manufacturing Research and development of software technology“. Thesis, 2015. http://ndltd.ncl.edu.tw/handle/53724513132024843689.
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碩士國立中正大學
機械工程學系暨研究所
103
Today light curing technology developed with DLP projection light irradiation resin molding, the software required to generate the mask layer after model sliced, and with the machine as a mask correction. This paper will outline slicing layers according to coloring algorithms convert the mask pattern can be output to the DLP's 3D printing machine, mask and explore the process and result. This paper in the experiment, the mask is output to the machine experiment 12 groups via measurements and model calculations can be learned before the model uncompensated X axis zoom + 0.665%, Y-axis shrink -3.446%, and compensated by experimental measurements available X-axis zoom revised to + 0.273%, Y-axis shrink revised to -0.266%, X-axis correction margin of 0.392%, Y-axis correction margin of 3.18% The actual measurement compensated and uncompensated result that prior to the actual measurement, and before the original model error compensation box X axis 0.0998mm, Y axis 0.507mm, after compensating for the original model with the X-axis error 0.041mm, Y axis 0.04mm, compensation before and after the actual margin of error correction X axis is 0.0588mm, Y axis 0.467mm
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Canas, Ricardo Manuel da Silva. „Simoldes : the impact of additive manufacturing : 3D printing technology“. Master's thesis, 2014. http://hdl.handle.net/10400.14/16813.
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This
case
study
provides
an
overview
of
the
automobile
industry,
Simoldes
and
the
emergence
of
additive
manufacturing
technology,
also
known
as
3D
printing.
The
goal
of
this
master’s
degree
dissertation
is
to
conduct
a
strategic
analysis
of
Simoldes
taking
into
account
the
implications
of
incorporating
additive
manufacturing
technology
into
the
company´s
value
chain.
Understanding
what
advantages
additive
manufacturing
can
bring
to
Simoldes
strategy
is
fundamental.
Different
management
approaches
regarding
this
technology
are
provided
at
the
end
of
the
case.
Should
Simoldes
not
adopt
this
technology,
or
should
they
proactively
incorporate
additive
manufacturing
into
its
manufacturing
process?
This
is
the
main
subject
to
the
discussed
on
this
master’s
dissertation
thesis.
In
the
teaching
notes
section,
there
is
a
set
of
questions
with
a
proposed
resolution.
From
this
analysis,
it
is
possible
to
see
several
benefits
that
additive
manufacturing
can
bring
to
Simoldes.
Efficiencies
in
time
and
costs
are
the
main
potential
advantages.
Incorporation
of
this
technology
into
Simoldes
manufacturing
processes
is
the
recommended
outcome
of
this
case
study.Este caso de estudo mostra uma visão geral da indústria automóvel, da empresa Simoldes e do surgimento da tecnologia de fabricação aditiva, também conhecida como a impressão 3D . O objetivo desta dissertação de mestrado é a da realização de uma análise estratégica da empresa Simoldes tendo em conta as implicações da incorporação da tecnologia de fabricação aditiva na sua cadeia de valor. Entender as vantagens que esta tecnologia pode trazer para a Simoldes é um dos aspectos fundamentais. Diferentes abordagens em relação a esta tecnologia são fornecidos no final do caso. Deverá a Simoldes não adotar essa tecnologia , ou deverá incorporar de forma proactiva a fabricação aditiva nos seus processos de produção ? Este é o principal aspecto a ser discutido nesta dissertação de mestrado. Na secção de notas de ensino , há um conjunto de perguntas com uma proposta de resolução. A partir desta análise , é possível observar vários benefícios que a fabricação aditiva pode trazer para a Simoldes. Ganhos de eficiência no tempo e nos custos são as principais e potenciais vantagens. A incorporação desta tecnologia em processos de fabricação Simoldes é o resultado recomendado deste caso de estudo.
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Malmelöv, Andreas. „Modeling of Additive Manufacturing with Reduced Computational Effort“. Thesis, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-58394.
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49
Lai, En-Yu, und 賴恩宇. „The Rapid Development of Injection Mold by Additive Manufacturing Technology“. Thesis, 2018. http://ndltd.ncl.edu.tw/handle/3wj34b.
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碩士大葉大學
工業工程與管理學系
106
Plastic products have widely used in our life; it becomes one of an essential material used in daily life. Injection molding procedure, advantages of rapid mass production and design flexibility, is usually employed to produce plastic products. However, a new injection mold needs weeks to months to make, how to manufacture an injection mold rapidly to short product lifecycle and get ahead of the market has become a critical issue. Therefore, in this study the rapid additive manufacturing technology was conducted to develop the injection mold. It was divided into two parts to fast manufacture injection mold and produce products quickly. One is standard external metal mold, and the other is inner mold with fused deposition modeling (FDM) technology. Finite element method (FEM) software, Modex 3D, and ANSYS Workbench were conducted in this study. To prevent the massive deformation and distortion of the plastic product, Modex 3D was used to analyze the mold deformation relation between the injection pressure and time; ANSYS Workbench was employed to static analysis of mold strength in mold cooling, and thermal transient analysis of injection pressure, time, and deformation of the injection mold. The results of the rapid development of injection mold by additive manufacturing technology show that the production time of the inner mold with FDM was made in one week. Under 18 MPa of the injection pressure, the deformation percentage of the injection mold and plastic product are 4.68% and 7.2%, respectively.
50
Tseng, Po-Hsiang, und 曾柏翔. „Application of Laser Additive Manufacturing Technology in Liquid Cooling System“. Thesis, 2018. http://ndltd.ncl.edu.tw/handle/wgtdqq.
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碩士國立交通大學
機械工程系所
106
This study experimentally investigated the heat transfer and pressure drop performance of the novel designed liquid-cooled heat sink. There are five heat sinks that were used for testing in the study, including the chevron-type corrugation channel, the homogeneous porous channel, non-uniform pore density distribution porous channel, non-uniform pore density distribution with augmented fin efficiency design porous channel, the different pore density distribution (encryption inlet) porous channel. The heat sinks are made of titanium alloy via 3-D printing. With water as the working fluid, the volumetric flow rate ranged from 0.3 L/min to 7.2 L/min. The supplied power is 250 W. Test results show that BCC structure can be made available by 3-D printing with high mechanical strength. The structure can be operated under high flow rate with a pressure drop being lower than traditional metal foam. Test results also indicate that the chevron-type corrugation channel works nicely at low flow rates, and the newly designed porous channel performs more efficiently works well at medium and high flow rates. Comparisons are made between the newly designed porous channel and the chevron-type corrugation channel under pumping power of 1W. It is found that the thermal resistance of homogeneous structure is decreased about 55%. Thermal resistance is decreased about 67% via changing pore density distribution. Yet thermal resistance can be reduced about 82% via changing pore density distribution and improving fin efficiency design. However, a more dense structure at the inlet can not ease the mal-distribution problem completely, leading to a maximum thermal resistance occurring in the opposite corner side of the outlet. Maximum thermal resistance is higher than average thermal resistance about 66%-109% under the same operating condition.