Tesis sobre el tema "Material manufacturing"
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1
Braconnier, Daniel J. "Materials Informatics Approach to Material Extrusion Additive Manufacturing". Digital WPI, 2018. https://digitalcommons.wpi.edu/etd-theses/204.
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Process-structure-property relationships in material extrusion additive manufacturing (MEAM) are complex, non-linear, and poorly understood. Without proper characterization of the effects of each processing parameter, products produced through fused filament fabrication (FFF) and other MEAM processes may not successfully reach the material properties required of the usage environment. The two aims of this thesis were to first use an informatics approach to design a workflow that would ensure the collection of high pedigree data from each stage of the printing process; second, to apply the workflow, in conjunction with a design of experiments (DOE), to investigate FFF processing parameters. Environmental, material, and print conditions that may impact performance were monitored to ensure that relevant data was collected in a consistent manner. Acrylonitrile butadiene styrene (ABS) filament was used to print ASTM D638 Type V tensile bars. MakerBot Replicator 2X, Ultimaker 3, and Zortrax M200 were used to fabricate the tensile bars. Data was analyzed using multivariate statistical techniques, including principal component analysis (PCA). The magnitude of effect of layer thickness, extrusion temperature, print speed, and print bed temperature on the tensile properties of the final print were determined. Other characterization techniques used in this thesis included: differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and scanning electron microscopy (SEM). The results demonstrated that printer selection is incredibly important and changes the effects of print parameters; moreover, further investigation is needed to determine the sources of these differences.
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Shahbazi, Sasha. "MATERIAL EFFICIENCY MANAGEMENT IN MANUFACTURING". Licentiate thesis, Mälardalens högskola, Innovation och produktrealisering, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-28004.
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Material efficiency is a key solution to provide a reduction in the total environmental impact of global manufacturing, which contributes to avoid generating larger volumes of industrial waste, to reduce extracting and consuming ever more resources and to decrease energy demand and carbon emissions. However, the area of material efficiency in manufacturing has been under-researched and related knowledge is limited. The research objective of this thesis is to contribute to the existing body of knowledge regarding material efficiency in manufacturing - to increase understanding, describe the existing situation and develop support for improvement. This thesis focuses on value of process and residual materials in material efficiency: to increase homogenous quality of generated waste with higher segregation rate, decreasing the amount of material becoming waste and reduce total virgin raw material consumption without influencing the function and quality of a product or process. To achieve the objective, material efficiency strategies, existing state of material efficiency in manufacturing and barriers that avert higher material efficiency improvement have been investigated. The results are supported by four structured literature reviews and two [MW1] empirical multiple case studies at large global manufacturing companies in Sweden, mainly automotive. Empirical studies include observations, interviews, waste stream mapping, waste sorting analysis, environmental report reviews and walkthroughs in companies to determine the material efficiency and industrial waste management systems. The empirical results revealed that material efficiency improvement potential of further waste segregation to gain economic and environmental benefits is still high. Determining different waste segments and relative fractions along with calculating material efficiency performance measurements facilitate improvements in material efficiency. In addition to attempts for waste generation reduction, avoiding blending and correct segregation of different waste fractions is an essential step towards material efficiency. The next step is to improve the value of waste fractions i.e. having more specific cost-effective fractions. Waste Flow Mapping proves to be an effective practical tool to be utilized at manufacturing companies in order to check and explore the improvement opportunities. In addition, a number of barriers that hinder material efficiency was identified. The most influential material efficiency barriers are Budgetary, Information, Management and Employees. The majority of identified material efficiency barriers are internal, originate inside the company itself and are dependent upon the manufacturing companies’ characteristics. As a result, management and employees’ attitude, environmental knowledge and environmental motivation, as well as their internal communication and information sharing, and companies’ core value and vision are the enablers for material efficiency improvement.MEMIMAN
INNOFACTURE - innovative manufacturing development
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Wan, Yen-Tai. "Material transport system design in manufacturing". Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-03282006-231022/.
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Thesis (Ph. D.)--Industrial and Systems Engineering, Georgia Institute of Technology, 2006.Dr. Yih-Long Chang, Committee Member ; Dr. Martin Savelsbergh, Committee Member ; Dr. Leon McGinnis, Committee Co-Chair ; Dr. Gunter Sharp, Committee Chair ; Dr. Doug Bodner, Committee Member ; Dr. Joel Sokol, Committee Member.
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Goel, Anjali 1978. "Economics of composite material manufacturing equipment". Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/31096.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000.Includes bibliographical references (p. 43).
Composite materials are used for products needing high strength-to-weight ratios and good corrosion resistance. For these materials, various composite manufacturing processes have been developed such as Automated Tow Placement, Braiding, Diaphragm Forming, Resin Transfer Molding, Pultrusion, Autoclave Curing and Hand Lay Up. The aim of this paper is to examine the equipment used for these seven processes and to produce a cost analysis for each of the processes equipment. Since many of these processes are relatively new or are fairly costly and specified to the customers need, much of the equipment is custom made to meet the requirements of the part being produced. Current pricing information for individual custom-built machines, as well as standard machinery has been provided here.
by Anjali Goel.
S.B.
5
Mullen, T. D. "Material flow control in complex manufacturing systems". Thesis, University of Strathclyde, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360792.
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Karmakar, Mattias. "Additive Manufacturing Stainless Steel for Space Application". Thesis, Luleå tekniska universitet, Materialvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-72901.
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Zhu, Wenkai y 朱文凱. "Concurrent toolpath planning for multi-material layered manufacturing". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B42841446.
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Zhu, Wenkai. "Concurrent toolpath planning for multi-material layered manufacturing". Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B42841446.
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Ek, Kristofer. "Additivt tillverkat material". Thesis, KTH, Maskinkonstruktion (Inst.), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-152230.
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SammanfattningDet här projektet behandlar området Additiv Tillverkning (AM) för metalliska material och undersöker om det är lämpligt att använda vid produktion inom flygindustrin. AM är en relativt ny tillverkningsmetod där föremål byggs upp lager för lager direkt ifrån en datormodell. Teknikområdet tillåter i många fall större konstruktionsfriheter som möjliggör tillverkning av mer viktoptimerade och funktionella artiklar. Andra fördelar är materialbesparing och kortare ledtider vilket har ett stort ekonomiskt värde.En omfattande litteraturstudie har gjorts för att utvärdera alla tekniker som finns på marknaden och karakterisera vad som skiljer de olika processerna. Även maskiners prestanda och kvalité på tillverkat material utvärderas, och för varje teknik listas möjligheter och begränsningar. Teknikerna delas grovt upp i pulverbäddsprocesser och material deposition-processer. Pulverbäddsteknikerna tillåter större friheter i konstruktion, medan material deposition-processerna tillåter tillverkning av större artiklar. Den vanligaste energikällan är laser som ger ett starkare men mer sprött material än de alternativa energikällorna elektronstråle och ljusbåge.Två specifika tekniker har valts ut för att undersöka närmare i detta projekt. Electron Beam Melting (EBM) från Arcam och Wire fed plasma arc direct metal deposition från Norsk Titanium (NTiC). EBM är en pulverbäddsprocess som kan tillverka färdiga artiklar i begränsad storlek då låga krav ställs på toleranser och ytfinhet. NTiC använder en material deposition-process med en ljusbåge för att smälta ner trådmaterial till en nära färdig artikel. Den senare metoden är mycket snabb och kan tillverka stora artiklar, men måste maskinbearbetas till slutgiltig form. En materialundersökning har genomförts där Ti6Al4V-material från båda teknikerna har undersökts i mikroskop och testats för hårdhet. För EBM-material har även ytfinhet och svetsbarhet undersökts då begränsad byggvolym i många fall kräver fogning. Materialen har egenskaper bättre än gjutet material med avseende på styrka och duktilitet, men inte lika bra som valsat material. Provning visar att skillnaden på mekaniska egenskaper i olika riktningar är liten även fast materialet har en inhomogen makrostruktur med kolumnära korn i byggriktningen. EBM ger en finare mikrostruktur och ett starkare material och, tillsammans med de ökade konstruktionsfriheterna, så är det den tekniken som är bäst lämpad för flygplansartiklar då svetsbarheten är god och det finns möjlighet att bearbeta ytan till slutgiltigt krav.Nyckelord: Additiv Tillverkning, Flygteknik, TitanAbstractThis project treats Additive Manufacturing (AM) for metallic material and the question if it is suitable to be used in the aeronautics industry. AM is a relatively new production method where objects are built up layer by layer from a computer model. The art of AM allows in many cases more design freedoms that enables production of more weight optimized and functional articles. Other advantages are material savings and shorter lead times which have a large economic value.An extensive literature study has been made to evaluate all techniques on the market and characterize what separates the different processes. Also machine performance and material quality is evaluated, and advantages and disadvantages are listed for each technique. The techniques are widely separated in powder bed processes and material deposition processes. The powder bed techniques allow more design freedom while the material deposition techniques allow production of large articles. The most common energy source is laser that gives a harder and more brittle material than the alternative energy sources electron beam and electric arc.Two specific techniques have been selected to investigate further in this project. Electron Beam Melting (EBM) from Arcam and Wire fed plasma arc direct metal deposition from Norsk Titanium (NTiC). EBM is a powder bed process that can manufacture finished articles in limited size when no requirements are set on tolerances and surface roughness. NTiC uses a material deposition process with electric arc to melt wire material to a near-net shape. The latter method is very fast and can produce large articles, but have to be machined to finished shape. A material investigation have been made where Ti6Al4V-material from both techniques have been investigated in microscope and tested for hardness. For the EBM-material have also surface roughness and weldability been investigated since the limited building volume often requires welding. The materials have mechanical properties better than cast material with respect to strength and ductility, but not as good as wrought material. Test results show that the difference in mechanical properties in different directions is small, even though the material has an inhomogeneous macrostructure with columnar grains in the building direction. The EBM-material has a finer microstructure and a stronger material and, in combination with improved design freedom, this technique is most suitable for aerospace articles when the weldability is good and it is possible to surface work where requirements of the surface roughness are set.Keywords: Additive Manufacturing, Aeronautics, Titanium
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Cheung, Hoi-hoi y 張凱凱. "A multi-material virtual prototyping system". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B29727716.
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Mummareddy, Bhargavi. "Additive Manufacturing Processes for High-Performance Ceramics: Manufacturing - Mechanical and Thermal property Relationship". Youngstown State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1629131959379597.
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Liu, Yihan. "Transformative Manufacturing of 2D Material for THZ Resonator". University of Dayton / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1596814704289023.
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Lagodimos, Athanasios G. "Protective inventories in manufacturing systems". Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335161.
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Middleton, Joanne F. "Integrated material management for metallic melting shops". Thesis, Cranfield University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385809.
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Ek, Kristofer. "Additive Manufactured Material". Thesis, KTH, Maskinkonstruktion (Inst.), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-156887.
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This project treats Additive Manufacturing (AM) for metallic material and the question if it is suitable to be used in the aeronautics industry. AM is a relatively new production method where objects are built up layer by layer from a computer model. The art of AM allows in many cases more design freedoms that enables production of more weight optimized and functional articles. Other advantages are material savings and shorter lead times which have a large economic value. An extensive literature study has been made to evaluate all techniques on the market and characterize what separates the different processes. Also machine performance and material quality is evaluated, and advantages and disadvantages are listed for each technique. The techniques are widely separated in powder bed processes and material deposition processes. The powder bed techniques allow more design freedom while the material deposition techniques allow production of large articles. The most common energy source is laser that gives a harder and more brittle material than the alternative energy sources electron beam and electric arc. Two specific techniques have been selected to investigate further in this project. Electron Beam Melting (EBM) from Arcam and Wire fed plasma arc direct metal deposition from Norsk Titanium (NTiC). EBM is a powder bed process that can manufacture finished articles in limited size when no requirements are set on tolerances and surface roughness. NTiC uses a material deposition process with electric arc to melt wire material to a near-net shape. The latter method is very fast and can produce large articles, but have to be machined to finished shape. A material investigation have been made where Ti6Al4V-material from both techniques have been investigated in microscope and tested for hardness. For the EBM-material have also surface roughness and weldability been investigated since the limited building volume often requires welding. The materials have mechanical properties better than cast material with respect to strength and ductility, but not as good as wrought material. Test results show that the difference in mechanical properties in different directions is small, even though the material has an inhomogeneous macrostructure with columnar grains in the building direction. The EBM-material has a finer microstructure and a stronger material and, in combination with improved design freedom, this technique is most suitable for aerospace articles when the weldability is good and it is possible to surface work where requirements of the surface roughness are set. Keywords: Additive Manufacturing, Aeronautics, TitaniumDet här projektet behandlar området Additiv Tillverkning (AM) för metalliska material och undersöker om det är lämpligt att använda vid produktion inom flygindustrin. AM är en relativt ny tillverkningsmetod där föremål byggs upp lager för lager direkt ifrån en datormodell. Teknikområdet tillåter i många fall större konstruktionsfriheter som möjliggör tillverkning av mer viktoptimerade och funktionella artiklar. Andra fördelar är materialbesparing och kortare ledtider vilket har ett stort ekonomiskt värde. En omfattande litteraturstudie har gjorts för att utvärdera alla tekniker som finns på marknaden och karakterisera vad som skiljer de olika processerna. Även maskiners prestanda och kvalité på tillverkat material utvärderas, och för varje teknik listas möjligheter och begränsningar. Teknikerna delas grovt upp i pulverbäddsprocesser och material deposition-processer. Pulverbäddsteknikerna tillåter större friheter i konstruktion, medan material deposition-processerna tillåter tillverkning av större artiklar. Den vanligaste energikällan är laser som ger ett starkare men mer sprött material än de alternativa energikällorna elektronstråle och ljusbåge. Två specifika tekniker har valts ut för att undersöka närmare i detta projekt. Electron Beam Melting (EBM) från Arcam och Wire fed plasma arc direct metal deposition från Norsk Titanium (NTiC). EBM är en pulverbäddsprocess som kan tillverka färdiga artiklar i begränsad storlek då låga krav ställs på toleranser och ytfinhet. NTiC använder en material deposition-process med en ljusbåge för att smälta ner trådmaterial till en nära färdig artikel. Den senare metoden är mycket snabb och kan tillverka stora artiklar, men måste maskinbearbetas till slutgiltig form. En materialundersökning har genomförts där Ti6Al4V-material från båda teknikerna har undersökts i mikroskop och testats för hårdhet. För EBM-material har även ytfinhet och svetsbarhet undersökts då begränsad byggvolym i många fall kräver fogning. Materialen har egenskaper bättre än gjutet material med avseende på styrka och duktilitet, men inte lika bra som valsat material. Provning visar att skillnaden på mekaniska egenskaper i olika riktningar är liten även fast materialet har en inhomogen makrostruktur med kolumnära korn i byggriktningen. EBM ger en finare mikrostruktur och ett starkare material och, tillsammans med de ökade konstruktionsfriheterna, så är det den tekniken som är bäst lämpad för flygplansartiklar då svetsbarheten är god och det finns möjlighet att bearbeta ytan till slutgiltigt krav. Nyckelord: Additiv Tillverkning, Flygteknik, Titan
16
Nanjappa, Jagadish. "Web-based dynamic material modeling". Ohio : Ohio University, 2002. http://www.ohiolink.edu/etd/view.cgi?ohiou1174918633.
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Gong, Dah-Chuan. "A metalmodel of asynchronous material transport". Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/32868.
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Asef-Vaziri, Ardavan. "A loop material flow system design for manufacturing plants". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ27871.pdf.
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Silva, Rinaldo J. "Information processing in designing manufacturing systems with material handling". Thesis, Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/25110.
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Ho, Joseph Chi-Chen 1975. "Surface space : digital manufacturing techniques and emergent building material". Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/67170.
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Thesis (M.Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2002.Includes bibliographical references (p. 74-76).
This thesis explores tectonic possibilities of new material and forming techniques. The design process is catalyzed by experimenting different configurations of the material.This project attempts to develop inventive ways to use polymeric material. Incorporating both digital and hand based tools, the project will focus on the process of casting and molding polyurethane based rubber. Instead of looking at the macro level of a building, the thesis should be viewed as a research based project that investigates assemblies at the domain of building surface. Based on this premise, the goal is to find how the tectonic expression at the scale of architectural details can inspire creative use of the material. The framework of this thesis should be regarded as an open-ended process of discovery. Future research and innovation can be continued with respect to similar focus. The goal of this thesis is to engage design problems from innovations of material and techniques.
Joseph Chi-Chen Ho.
M.Arch.
21
Chandra, Vikash M. Eng Massachusetts Institute of Technology y Michael Tulley. "Raw material inventory strategy for make-to-order manufacturing". Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/107523.
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Thesis: M. Eng. in Logistics, Massachusetts Institute of Technology, Supply Chain Management Program, 2016."June 2016." Cataloged from PDF version of thesis.
Includes bibliographical references (pages 63-64).
What is the appropriate raw material inventory strategy for a make-to-order manufacturing company? As companies grow in size and the business environment changes over time, many companies adapt their operating policies to remain competitive. However, some policies, such as raw material inventory policies, are left untouched as "legacies" of the company's past due to lower priorities or lack of adequate data. These raw material inventory policies are of particular importance to manufacturing firms, especially those that often operate at maximum capacity or have seasonality in demand. This research proposes a raw material inventory policy evaluation tool that allows a company to understand how certain key performance indicators are affected by various changes in its inventory policy and helps the company devise a strategy. This evaluation tool can then guide the company towards a better inventory policy in the absence of cost information and shows the results in terms of number of events. The company can then adjust various replenishment policies depending on the product's demand characteristics. In addition, the research demonstrates that inventory policy changes can be used to partially overcome supplier service level declines and demand variability.
by Vikash Chandra and Michael Tully.
M. Eng. in Logistics
22
Bandiera, Nicholas Graham. "Hybrid inkjet and direct-write multi-material additive manufacturing". Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/111774.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2017.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 77-79).
Recently there has been a trend towards combining multiple forms of additive manufacturing together for increased functionality, freedom and efficiency. In this work, two forms of multiple-material additive manufacturing technologies - inkjet and direct-ink writing - are combined in a hybrid system. Several advantages are realized due to the increased material library and geometric freedom as a result of new printing modalities. Initially, models of each process are reviewed and the processes are evaluated for compatibility. Then, the precision machine design of a passively-indexed, carousel-style, syringe tool holder is completed. An error budget employing Homogeneous Transformation Matrices was maintained to estimate the tooltip errors. In order to register these two non-contact printing processes, a unique approach to their registration to a common global origin was necessary. A single non-contact optical CCD micrometer is used to register the three spatial coordinates of the syringe tooltip. Measurements are performed to characterize the repeatability of the nozzle registration scheme and the constructed gantry and carousel system, which well exceeds the requirements and the predictions from the conservative error budget. This novel system can print with a wide array of inks, including those that solidify via polymerization or crosslinking, two part chemistries, solvent evaporation or sintering, as well as liquids, gels and pastes. These materials can have a wide range of mechanical properties and functionalities, for example electrical conductivity or force sensitive resistivity. Models for the extrudate flow rate are used alongside experimental determination of the extrudate cross-section to ensure accurate process congruence. Finally, printed results demonstrate the various printing techniques, highlight the expanded material library, and display novel assemblies not possible with conventional additive processes. One such example is a fully printed pressure sensor array.
by Nicholas Graham Bandiera.
S.M.
23
KHAGHANI, ALI. "MANUFACTURING OF MATERIAL BASED HYDROGEN FUEL FOR LIGHTWEIGHT VEHICLES". Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/613155.
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Vehicles powered by hydrogen fuel cells store hydrogen as a cooled liquid at 20 degrees kelvin
or a compressed gas at 10,000 pounds per square inch. An alternative that eliminates the need
for these extremes of temperature and pressure is to heat a compound containing covalently
bonded hydrogen, causing it to release the hydrogen to the fuel cell. Ammonia borane, which is
stable at ambient conditions, requires minimal energy for dehydrogenation, and is rich in
hydrogen, is a possible storage medium for hydrogen. If a viable storage system could be
engineered, demand for ammonia borane as a source of hydrogen would increase. The goal of
this project is to develop a processing plant and to optimize design specifications for scaling up
processing of ammonia borane through the metathesis reaction pathway. Optimization of
individual unit operations was determined using quality-by-design concepts, which allowed the
team to confirm scalability, design limitations, and competitive market pricing. The final design
involves the application of two mixers, two reactors, and four separators. The plant design
should yield 99 percent pure ammonia borane.
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Bandiera, Nicholas Graham. "Hybrid inkjet and direct-write multi-material additive manufacturing". Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111774.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2017.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 77-79).
Recently there has been a trend towards combining multiple forms of additive manufacturing together for increased functionality, freedom and efficiency. In this work, two forms of multiple-material additive manufacturing technologies - inkjet and direct-ink writing - are combined in a hybrid system. Several advantages are realized due to the increased material library and geometric freedom as a result of new printing modalities. Initially, models of each process are reviewed and the processes are evaluated for compatibility. Then, the precision machine design of a passively-indexed, carousel-style, syringe tool holder is completed. An error budget employing Homogeneous Transformation Matrices was maintained to estimate the tooltip errors. In order to register these two non-contact printing processes, a unique approach to their registration to a common global origin was necessary. A single non-contact optical CCD micrometer is used to register the three spatial coordinates of the syringe tooltip. Measurements are performed to characterize the repeatability of the nozzle registration scheme and the constructed gantry and carousel system, which well exceeds the requirements and the predictions from the conservative error budget. This novel system can print with a wide array of inks, including those that solidify via polymerization or crosslinking, two part chemistries, solvent evaporation or sintering, as well as liquids, gels and pastes. These materials can have a wide range of mechanical properties and functionalities, for example electrical conductivity or force sensitive resistivity. Models for the extrudate flow rate are used alongside experimental determination of the extrudate cross-section to ensure accurate process congruence. Finally, printed results demonstrate the various printing techniques, highlight the expanded material library, and display novel assemblies not possible with conventional additive processes. One such example is a fully printed pressure sensor array.
by Nicholas Graham Bandiera.
S.M.
25
Kinard, Janet. "Material systems for rapid manufacture of composite structures". Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/16844.
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Krishnakumar, Karthikeyan. "Material and processes selection in conceptual design". Texas A&M University, 2003. http://hdl.handle.net/1969.1/1337.
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Materials and manufacturing processes are an integral part of the design of a product. The need to combine materials and manufacturing processes selection during the early stages of the design has previously been realized. The work that generally attracts the most attention is by M.F. Ashby. This methodology, like others, concentrates on materials and manufacturing processes selection after the conceptual design is completed and before moving into embodiment design.
The disadvantage of waiting until the conceptual design is completed to address materials and manufacturing processes is that the designer cannot search for conceptual solutions when dealing with issues relating to the materials and manufacturing processes domains. By not considering these issues early on in the design process, the scope for innovation is reduced and this results in the designer being fixated on the configuration at hand. It is well recognized that this is not the best way to address a design challenge and an even worse approach to innovation.
The basic framework for which enhancements and improvements are suggested is the design methodology practiced and taught by the members of the Institute for Innovation and Design in Engineering (IIDE) at Texas A&M University. Conceptual design is very much a part of the IIDE design process; but the current format concentrates on functional parameters and how to search for conceptual solutions for these, and does not highlight materials and manufacturing issues in the preliminary design stages where it could be most helpful.
The work documented in this thesis is an attempt to ensure that there is no disconnect between function oriented design and the materials and manufacturing processes that are applicable to that design. The core of the thesis is to incorporate a thought process which will help the designer during conceptual design phase to:
1. Consciously question if there materials and manufacturing issues; 2. Identify critical parameters in both of these domains; and 3. Search for conceptual solutions to these identified critical parameters.
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El, Mouhib Sabrina. "Effect of Stainless Steel Additive Manufacturing On Heat Conductivity and Urea Deposition". Thesis, KTH, Materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-287314.
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Hydroforming is the manufacturing process that Scania uses to produce exhaust pipes with complex shape and high durability. Selective Laser Melting is the process used by designers to print prototype pipes and perform emissions tests before mass production. Results from previous tests at Scania showed superior performance of 3D printed pipes compared to hydroformed components during emissions test as the 3D printed pipes were able to transfer heat faster than hydroformed pipes. To understand the reason behind this mismatch, the effect of selective laser melting parameters on energy density, relative density, grain size and thermal conductivity are investigated. These properties have direct impact on heat transfer. Ten samples were fabricated using the same laser power and layer thickness but different combinations of scanning speed and hatch distance. Samples were then subject to microstructural analysis using an optical microscope and average grain size measurement using image analysis software called Imagej. The density of each sample was measured using the Archimedes method. Moderate correlation is found between energy density and relative density. No ranking of the selective laser melting parameters with respect to forming the highest density was achieved because of the high uncertainties involved with the density measurement technique. Thermal conductivity was measured us- ing the one dimensional heat flow equation with an appropriate experimental set up. Thermal conductivity seems to be more influenced by relative density and direction of printing layers than the energy density and grain size. This conclusion is not statistically significant due to high uncertainty involved in the measurement of thermal conductivity. More advanced and accurate tech- nologies need to be used in the future to measure both density and thermal conductivity in order to find the most suitable selective laser melting parameters for Scania’s prototype pipes. The findings of this research can be used as a foundation for future research related to urea deposition on 3D printed pipes.Hydroforming är den tillverkningsprocess Scania använder för att producera avgasrör som har en komplex form och hög hållbarhet. Selektiv lasersmältning är den process som används av konstruktörer för att skriva ut prototyprör och utföra utsläppstester före massproduktion. Resultat från tidigare utsläppstes- ter på Scania visade en överlägsen prestanda för 3D-tryckta rör jämfört med hydroformade komponenter, eftersom 3D-tryckta rör kunde överföra värme snabbare än hydroformade rör. För att förstå orsaken bakom denna skillnad undersöks effekten av selektiva lasersmältningsparametrar som energitäthet, relativ densitet, kornstorlek och värmeledningsförmåga. Dessa egenskaper har direkt inverkan på värmeöverföringen. 10 prover tillverkades med samma laserkraft och skikttjocklek, men med olika kombinationer av skanningshastighet och kläckavstånd. Proverna utsattes sedan för en mikrostrukturell analys med hjälp av ett optiskt mikroskop, samt genomsnittlig kornstorleksmätning med hjälp av bildanalysprogramvaran Imagej. Densiteten för varje prov mättes med Archimedesmetoden. Måttlig korrelation kunde identifieras mellan energitätheten och relativ densitet. Ingen rangordning av de selektiva lasersmältningsparametrarna med avseende på bildning av den högsta densiteten uppnåddes på grund av de höga osäkerhetsfaktorer som är involverade i densitetsmättekniken. Värmeledningsförmågan mättes med hjälp av den endimensionella värmeflödesekvationen, med en lämplig experimentell uppställning. Värmeledningsförmågan tycks påverkas mer av tryckskiktens relativa densitet och riktning än energidensiteten och kornstorleken. Denna slutsats är inte statistiskt signifikant på grund av hög osäkerhet i mätningen av värmeledningsförmåga. Mer avancerade och noggranna teknologier måste användas i framtiden för att mäta både densitet och värmeledningsförmåga, för att hitta de mest lämpliga selektiva lasersmältningsparametrarna för Scanias prototyprör.
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Cheung, Hoi-hoi. "A versatile multi-material virtual prototyping system". Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B3931988X.
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Boddapati, Venkata-Sandeep. "Exergy metric for the assessment of material processing in manufacturing". Lexington, Ky. : [University of Kentucky Libraries], 2006. http://lib.uky.edu/ETD/ukymseg2006t00493/thesis.pdf.
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Thesis (M.S.)--University of Kentucky, 2006.Title from document title page (viewed on October 31, 2006). Document formatted into pages; contains: xv, 138 p. : ill. (some col.). Includes abstract and vita. Includes bibliographical references (p. 134-137).
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Bonyadlou, Parmis y Anna Larsson. "The Development of Material Removal Solutions within Wind Blade Manufacturing". Thesis, KTH, Skolan för industriell teknik och management (ITM), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-223897.
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Boddapati, Venkata Sandeep. "EXERGY METRIC FOR THE ASSESMENT OF MATERIAL PROCESSING IN MANUFACTURING". UKnowledge, 2006. http://uknowledge.uky.edu/gradschool_theses/377.
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Exergy utilization calculations have been in the past repeatedly used to quantify the quality and quantity of energy used in thermal energy processes. This thesis is an attempt to derive a common language exergy utilization and compare for the first time two entirely different manufacturing processes, namely material processing by a mechanical method of straining of the material and simple heating of the same mass of the material using exergy utilization as a metric. The exergy utilization of material processing is determined by performed work and utilized heat transfer using 1) Ramberg-Osgood equation and 2) Lumped heat capacitance method. A comparison of these two methods is presented.
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O’Connor, Christopher. "Navy additive manufacturing: policy analysis for future DLA material support". Thesis, Monterey, California: Naval Postgraduate School, 2014. http://hdl.handle.net/10945/44634.
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Approved for public release; distribution is unlimitedThis project is a study of technology adoption theories and their application to Additive Manufacturing (AM) in the Navy and wider Department of Defense. It examines AM technology modalities and how they are used throughout the Navy. It also looks at the obstacles to wider implementation in the Navy and determines ways the Navy can overcome those and other considerations. Finally, it shows how the Defense Logistics Agency can support the AM through existing customer support programs.
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Arvidsson, Daniel. "Additive weld manufacturing and material properties effect on structural margins". Thesis, KTH, Lättkonstruktioner, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-243881.
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the FE analyses. Traditionally all parts are modeled with isotropic base material. Analyses are made on a part of the nozzle which includes both a butt weld and metal deposition and which is an interface to another part causing loads that has to be sustained by the weld and the MD. As a small part of this thesis was also a fatigue study made to a spot weld test specimen. In order to strengthen the nozzle to prevent structural damage, an outer layer is added to the already existing metal cone by material deposition, MD, or additive manufacturing. During the manufacturing process the material will indicate some degree of anisotropic properties. The key purpose of this thesis was to analyze how this anisotropic behaviour might affect the structural stiffener connected to this anisotropic material when exposed to a load at the end of the stiffener. Further analysis due to fatigue was also done to parts of the structure. The procedure was done by building a model and setting up the different anisotropic properties with help of a finite element program, Ansys. The material properties regarding the anisotropy of the material was changed and compared in order to see how it affected stresses and strains in the anisotropic material and it‘s surrounding materials. Further analysis was made to the properties of the weld such as the yield limit. The result would indicate that for loadings that did not generate plastic deformations, hence elastic deformations, there were no significant difference forthe different trial values of the yield ratios. However, the differences became parent when studying large plastic deformations. Variation of the Young’s modulus would show some differences in the monitored properties for both elastic and plastic deformations. Studies of degrading the welds yield limit would show no diffrences when elastic deformations were present, but would have a big impact when large plastic deformations were present. The J-values variations for the spotweld would indicate huge differences depending on the yield limits for the spotweld and base material.Detta examensarbete undersöker hur strukturella marginaler påverkas av att inkludera anisotropiska egenskaper för delar av en struktur samt att inkludera en svets som har andra material egenskaper såsom sträckgräns jämfört med anliggande material. Tidigare beräkningar är gjorda med antagandet att ingående material delar i strukturen är isotropiska. Analyserna omfattar styvhets bracketter som svetsas mot den anisotropiska delen av raket mun- stycket som är utsatta för laster som uppstår genom anslutning via andra delar på munstycket. En mindre analys gjordes också av en test detalj där två metall plattor svetsas ihop med hjälp av en punktsvets som förekommer på munstycket. Analyser med hänsyn till utmattning har också varit en del i detta arbete. För att styva upp raket munstyckets övre del så adderas ett yttre hölje genom additativ tillverkning. Denna tillverknings metod ger upphov till att det pålagda höljet uppvisar anisotropiska egenskaper. Inledningsvis så skapades en finit element model i programmet Ansys där det anisotropiska materialet definierades samt material egenskaper för svetsen. Beräkningar gjordes sedan utifrån att en last pålades i utkanten av styvhets bracketten och laster och töjningar noterades för varje beräknings cykel för dom olika delarna av strukturen. Resultaten visade att för laster som inte genererade några plastiska töjningar, dvs elastiska töjningar, att det inte var några skillnader när olika värden påsträckgränserna för den anisotropiska delen av strukturen ändrades. Däremot var ändringarna mer påtagliga när töjningarna var plastiska, dvs för större pålagda laster som genererade stora kvarvarande töjningar i strukturen. Variationer av styvheterna i den anisotropiska delen i strukturen visade skillnader för både elastiska och plastiska töjningar. Analyser där svetsens sträckgräns var mindre än närliggande material visade inga direkta skillnader för elastiska töjningar men visade stora skillnader för plastiska töjningar. J-integral värdena i punktsvetsen som funktion av pålagd last visade sig vara beroende av sträckgränsen för punktsvetsen samt för bas materialet.
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Valli, Giuseppe <1989>. "Metal additive manufacturing of soft magnetic material for electric machines". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amsdottorato.unibo.it/10131/1/Valli_Giuseppe_tesi.pdf.
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This research work concerns the application of additive manufacturing (AM) technologies in new electric mobility sectors. The unmatched freedom that AM offers can potentially change the way electric motors are designed and manufactured. The thesis investigates the possibility of creating optimized electric machines that exploit AM technologies, with potential in various industrial sectors, including automotive and aerospace. In particular, we will evaluate how the design of electric motors can be improved by producing the rotor core using Laser Powder Bed Fusion (LPBF) and how the resulting design choices affect component performance. First, the metallurgical and soft magnetic properties of the pure iron and silicon iron alloy parts (Fe-3% wt.Si) produced by LPBF will be defined and discussed, considering the process parameters and the type of heat treatment. This research shows that using LPBF, both pure iron and iron silicon, the parts have mechanical and magnetic properties different from the laminated ones. Hence, FEM-based modeling will be employed to design the rotor core of an SYN RM machine to minimize torque ripple while maintaining structural integrity. Finally, we suggest that further research should extend the field of applicability to other electrical devices.
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D'Amico, Tone Pappas. "Predicting Process and Material Design Impact on and Irreversible Thermal Strain in Material Extrusion Additive Manufacturing". Digital WPI, 2019. https://digitalcommons.wpi.edu/etd-dissertations/572.
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Increased interest in and use of additive manufacturing has made it an important component of advanced manufacturing in the last decade. Material Extrusion Additive Manufacturing (MatEx) has seen a shift from a rapid prototyping method harnessed only in parts of industry due to machine costs, to something widely available and employed at the consumer level, for hobbyists and craftspeople, and industrial level, because falling machine costs have simplified investment decisions. At the same time MatEx systems have been scaled up in size from desktop scale Fused Filament Fabrication (FFF) systems to room scale Big Area Additive Manufacturing (BAAM). Today MatEx is still used for rapid prototyping, but it has also found application in molds for fiber layup processes up to the scale of wind turbine blades. Despite this expansion in interest and use, MatEx continues to be held back by poor part performance, relative to more traditional methods such as injection molding, and lack of reliability and user expertise. In this dissertation, a previously unreported phenomenon, irreversible thermal strain (ITε), is described and explored. Understanding ITε improves our understanding of MatEx and allows for tighter dimensional control of parts over time (each of which speaks to extant challenges in MatEx adoption). It was found that ITε occurs in multiple materials: ABS, an amorphous polymer, and PLA, a semi-crystalline one, suggesting a number of polymers may exhibit it. Control over ITε was achieved by tying its magnitude back to part layer thickness and its directionality to the direction of roads within parts. This was explained in a detail by a micromechanical model for MatEx described in this document. The model also allows for better description of stress-strain response in MatEx parts broadly. Expanding MatEx into new areas, one-way shape memory in a commodity thermoplastic, ABS, was shown. Thermal history of polymers heavily influences their performance and MatEx thermal histories are difficult to measure experimentally. To this end, a finite element model of heat transfer in the part during a MatEx build was developed and validated against experimental data for a simple geometry. The application of the model to more complex geometries was also shown. Print speed was predicted to have little impact on bonds within parts, consistent with work in the literature. Thermal diffusivity was also predicted to have a small impact, though larger than print speed. Comparisons of FFF and BAAM demonstrated that, while the processes are similar, the size scale difference changes how they respond to process parameter and material property changes, such as print speed or thermal diffusivity, with FFF having a larger response to thermal diffusivity and a smaller response to print speed. From this experimental and simulation work, understanding of MatEx has been improved. New applications have been shown and rational design of both MatEx processes and materials for MatEx has been enabled.
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Wu, Yue. "Computer-aided design of cellular manufacturing layout". Thesis, Durham University, 1999. http://etheses.dur.ac.uk/1464/.
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Duttala, Satish. "Virtual material processing artificial intelligence based process selection". Ohio : Ohio University, 2002. http://www.ohiolink.edu/etd/view.cgi?ohiou1174590077.
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Vacha, Robin L. (Robin Lee). "Strategic raw material inventory optimization". Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/39688.
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Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering; in conjunction with the Leaders for Manufacturing Program at MIT, 2007.Includes bibliographical references (p. 77-78).
The production of aerospace grade titanium alloys is concentrated in a relatively small number of producers. The market for these materials has always been cyclical in nature. During periods of high demand, metal producers claim to operate near full capacity utilization. During periods of reduced demand, metal producers struggle to remain profitable. Additionally, the manufacturing processes for aerospace grade titanium alloys are capital intensive and require long lead-times in order to bring new capacity online. The combination of these factors often results in an inflexible titanium alloy raw material supply chain for Pratt & Whitney. At the same time, Pratt & Whitney experiences a variety of rare but disruptive events within the supply chain that affect their raw material requirements. Examples of these disruptive events include customer drop-in orders, manufacturing complications resulting in scrapped material, and planning deficiencies. In order to protect engine and spare part customers from delayed deliveries due to long lead-time raw materials, Pratt & Whitney holds a strategic inventory of various titanium alloy raw material.
(cont.) This thesis presents a mathematical model utilizing a Compound Poisson Process that can be used to optimize the amount of strategic titanium alloy raw material held by Pratt & Whitney. The associated mathematical algorithms were programmed into Microsoft Excel creating the Strategic Raw Material Inventory Calculator. Historical data was then collected and used with this unique tool to calculate service levels at current inventory levels as well as optimized inventory levels under various scenarios.
by Robin L. Vacha, Jr.
S.M.
M.B.A.
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Kareaga, Laka Zorion. "Dynamic stiffness and damping prediction on rubber material parts, FEA and experimental correlation". Thesis, London Metropolitan University, 2016. http://repository.londonmet.ac.uk/1125/.
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The final objective of the present work is the accurate prediction of the dynamic stiffness behaviour of complex rubber parts using finite element simulation tools. For this purpose, it becomes necessary to perform a complex rubber compound material characterisation and modelling work; this needs two important previous steps. These steps are detailed in the present document together with a theoretical review of viscoelastic visco-elasto-plastic models for elastomers. Firstly, a new characterisation method is proposed to determine the degree of cure of rubber parts. It is known that the degree of cure of rubbers bears heavily on their mechanical properties. This method consists of the correlation of swelling results to rheometer data achieving a good agreement. Secondly, the influence of the strain rate used in static characterisation tests is studied. In this step, a new characterisation method is proposed. The latter characterisation method will be used to fit extended hyperelastic models in Finite Element Analysis (FEA) software like ANSYS. The proposed method improves the correlation of experimental data to simulation results obtained by the use of standard methods. Finally, the overlay method proposed by Austrell concerning frequency dependence of the dynamic modulus and loss angle that is known to increase more with frequency for small amplitudes than for large amplitudes is developed. The original version of the overlay method yields no difference in frequency dependence with respect to different load amplitudes. However, if the element in the viscoelastic layer of the finite element model are given different stiffness and loss properties depending on the loading amplitude level, frequency dependence is shown to be more accurate compared to experiments. The commercial finite element program Ansys is used to model an industrial metal rubber part using two layers of elements. One layer is a hyper viscoelastic layer and the other layer uses an elasto-plastic model with a multi-linear kinematic hardening rule. The model, being intended for stationary cyclic loading, shows good agreement with measurements on the harmonically loaded industrial rubber part.
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Chianrabutra, Srisit. "A dry powder micro delivery device for multiple material additive manufacturing". Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/388046/.
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This thesis focuses on developing a novel material delivery device for a Multiple Material Additive Manufacturing (MMAM) system using a Dry Powder Printing (DPP) technique developed recently. The goal of the thesis was to study in detail the characteristic of a micro dispensing device utilizing ultrasonic vibration via a piezoelectric transducer, which was designed and constructed to handle a wide range of fine powder materials. The research systematically investigated the nature of the interaction between the device and the materials, which allowed the design and processing parameters to be understood. Experiments were conducted to explain the effects of the printing parameters on printing results so as to discover the basic characteristics of the new dry powder printing device. Moreover, weight measurements of the deposited powder, microscopy and image visualization was used to assess the behavior of the device. The device developed can successfully provide continuity, consistency and reliability of layer printing of multiple material powders. The results demonstrated that the device is capable of dispensing various types of fine powders, such as metals, polymers and ceramics, with particle sizes of between 14-72μm. The relative standard deviation of the device is less than 7%. The minimum mass flow rate can be reached at 0.14 mg/s for a cohesive powder such as a copper powder. The maximum moving speed is up to 50 mm/s for a free flowing powder such as a solder powder. Currently, the precise printing of micro geometries can be achieved up to a diameter as small as 85μm. Moreover, the study also reveals that the performance of the device mainly depends on the dispensing parameters (e.g. nozzle diameter, nozzle angle, and piezo electric position), material parameters (e.g. type, particle size, flowability) and process parameters (e.g. moving speed, signal voltage and standoff distance). High resolution printing by the device can be achieved by controlling these parameters. This work has shown that the dispenser can deliver different powders in very precise and small quantities at almost any designated position. This demonstrates the potential of this method for a multiple material delivery system for MMAM in the near future.
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Thor, Niklas. "Reduced manufacturing costs in medical device due to choice of material". Thesis, KTH, Materialvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210658.
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This degree project, conducted at Prevas AB, investigates if there is potential reduced production costs due to a change of material of the casing of a Digital Breathalyzer, with retained product characteristics. Considering the using of the product, 5 materials are presented and compared with respect to mechanical and thermal properties. A material analysis containing a merit value table is made and a new casing made of ABS/PC biocompatible plastic is chosen and redesigned with lowered production costs as a result. Return on Investment (ROI) in years and number of produced pieces is calculated with respect to necessary investments and potential reduced costs. With a production rate of 1000 and 4000 pieces per year the ROI is 11,2 and 2,76 years respectively, and ROI regarding production volume is 11 204 and 11 049 pieces respectively.Detta examensarbete, utfört på Prevas AB, undersöker om det går att minska produktionskostnaden genom att byta material av höljet på en digital alkoholmätare, med bibehållna produktegenskaper. Med produktens användande i åtanke presenteras och jämförs 5 alternativa material med avseende på mekaniska och termiska egenskaper. En materialanalys innehållande en meritvärdesanalys genomförs och ett nytt hölje av materialet ABS/PC biokompatibel väljs och designas om med en lägre produktionskostnad som resultat. Avkastningen mätt i år och antal producerade produkter kalkyleras med avseende på nödvändiga investeringar för projektet och potentiella minskade kostnader. Med en produktionsvolym på 1000 och 4000 per år blir avkastningen 11,2 och 2,76 år.Avkastningen i antal producerade produkter är 11 204 och 11 049.
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MURUGAN, VARUN. "Optimized Material Deposition for Extrusion-Based Additive Manufacturing of Structural Components". Doctoral thesis, Università degli studi di Pavia, 2022. http://hdl.handle.net/11571/1464786.
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Fang, Tao. "The integration of line loading and material handling". Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/30709.
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Kim, Do Hyung. "On the removal of material for polishing aspheric optics". Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343732.
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Arakatla, Adarsh. "Demand Driven Material Requirements Planning". Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-52797.
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Manufacturing industries used to develop their operation strategies focusing on the cost of manufacturing, high volume production, and stabilizing the customer demand. But due to advancements in technology and evolving customer needs, the market demand became highly volatile, dynamic and customers expected customization, low volume products, and faster deliveries. This evolution in customer needs has pushed the companies to improve their operating systems to be more flexible, agile, and adaptable to the market’s dynamic character. In order to effectively evolves themselves and achieve more flexibility, manufacturing companies had to implement effective manufacturing, planning, and control systems. The first breakthrough in planning systems came in the year 1975 where a systemic approach called material requirements planning was introduced by Orlicky. MRP has become the global for production planning and inventory management in manufacturing industries. Later, over the years, research on the planning systems has brought modifications in MRP and it was evolved into closed-loop MRP. Further into the late 1980’s availability of technology led to an introduction of a newly evolved system called the Manufacturing resource planning which resulted in a holistic approach in material planning involving, financial and accounting functions which improved the planning efficiency. Further advancement in technology resulted in advanced planning systems like Enterprise resource planning and Advanced planning and scheduling. On the contrary, though there has been a lot of advancement in technology and effective production planning methods, there are still discrepancies in obtained results when compared to theory. This is because the existing systems were based either solely on push production or pull production strategy. There is a lack of a hybrid system that includes the positives of both production strategies and negates the MRP conflict. However, in the year 2011, a new concept called demand-driven material requirements planning was introduced by Ptak & Smith, which was a fusion of the core MRP, theory of constraints, and Lean principles. Since the introduction DDMRP has seen an increase in implementation across industries which claimed a significant improvement in performance, on-time delivery, reduction in inventory, and reduced stock-outs. DDMRP has received very little attention in academia due to a lack of awareness among researchers and industries. A literature review approach was used to collect and analyze the data on DDMRP and its advantages. The objective of this thesis was to shed light on the process of DDMRP, its pros, and cons in implementing the new material planning system.
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Cheung, Hoi-hoi y 張凱凱. "A versatile multi-material virtual prototyping system". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B3931988X.
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Prins, William Santiago. "Computer simulation with sensitivity analysis of an advanced composite material manufacturing operation". Master's thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-02022010-020123/.
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Carrus, Brandon J. (Brandon Joseph) 1976. "The design and implementation of material and information flow for manufacturing systems". Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/9306.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000.Includes bibliographical references (p. 143-145).
Production systems are characterized by complex interactions between elements, both human and mechanical, with the goal to accomplish certain high-level manufacturing objectives. In order to ensure that the decisions made and the actions taken during the design and implementation of production systems are aligned with all of the objectives, a structured approach must be followed. In developing this structured approach, the axiomatic design methodology is applied, which provides the means for creating a hierarchy of system design objectives (what to do) and solutions (how to do it). From this conceptual design process, a Production System Design and Implementation (PSDI) Path is presented here. The PSDI Path guides the design through a series of steps in creating a successful physical manufacturing system environment in terms of the original high-level objectives. Defining the material and information flow in the system is a critical part of the PSDI path. Based on the steps in the PSDI Path and the design hierarchy, a procedure for constructing the material and information flow in the production system is developed. To aid in the design of material and information flow in the manufacturing system, a manufacturing system modeling environment is developed as the tool for visualizing and communicating the flow in the manufacturing system design. KEYWORDS: Lean Manufacturing, Value Stream Management, Manufacturing System Design, Production System Design, Cellular Manufacturing, Axiomatic Design.
by Brandon J. Carrus.
S.M.
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Kurppa, Kimmo. "A material and manufacturing technique comparison regarding the flooring of a bus". Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-38785.
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Purpose of this Master’s thesis is to compare the use of two alternative materials in the building the flooring of a bus. Currently the floors of Carrus Delta buses are built using plywood. Carrus Delta Oy wants to investigate the use of ready-made glass fibre elements instead of plywood elements which are custom cut at their factory in Lieto, Finland. Glass fibre is also presented as potential material of light-weight vehicles by Fenton and Hodkinson (2001).
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Johnson, Anita M. "PC-based MRP II software selection for the small hi-tech manufacturing firm". Online version, 2000. http://www.uwstout.edu/lib/thesis/2000/2000johnsona.pdf.
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