Dissertationen zum Thema „Metallic Additive Manufacturing“
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Coffigniez, Marion. „Additive manufacturing of 3D architectured metallic biomaterials by robocasting“. Thesis, Lyon, 2021. http://www.theses.fr/2021LYSEI007.
Der volle Inhalt der QuelleBeyond the personalisation aspect that it can bring to the medical field, additive manufacturing also gives access to the elaboration of cellular structures. These structures, with controlled porosity, make it possible both to modulate the mechanical properties of the object and to promote the cellular invasion necessary in tissue engineering. Among the metals commonly used in orthopaedic surgery, titanium alloys are those with the rigidity least distant from that of bone. This study therefore focuses on the development of structures made of Ti6-Al-4V, but also of magnesium since it has the advantage of being resorbable in the body. The scaffolds are obtained by robocasting, a process consisting of extruding, layer by layer, a pasty ink made up of powder and binder. The structures have then to be debinded and sintered at high temperature to achieve their final properties. For Ti-6Al-4V structures, a parametric study is carried out to evaluate the possibilities and limits of the process in terms of structures (and microstructures), chemical compositions and mechanical properties obtained. After optimisation, it is possible to obtain parts with two levels of interconnected porosities (intra-filament (interconnected) microporosity, beneficial for cell adhesion according to the literature, and drawn macropores), keeping a specific yield strength higher than that of bone (105 MPa.cm³/g) and a Young's modulus close to that of bone (28-30 GPa). An intra-filament porosity gradient can also be obtained by varying the powder size within a single part. Concerning magnesium, a binder compatible with the reactivity of the powder (ethanol base) has been identified and the first steps of the process (printing, debinding) are therefore quite feasible for this material. However, conventional sintering of (pure) magnesium is complicated by its reactivity. Alternative sintering methods are therefore being investigated (liquid phase sintering, Spark Plasma Sintering)
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.
Der volle Inhalt der QuelleEl, 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.
Der volle Inhalt der QuelleHydroforming 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.
Gullapalli, Vikranth. „Study of Metal Whiskers Growth and Mitigation Technique Using Additive Manufacturing“. Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc804972/.
Der volle Inhalt der QuelleZavala, Arredondo Miguel Angel. „Diode area melting : use of high power diode lasers in additive manufacturing of metallic components“. Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/18953/.
Der volle Inhalt der QuelleHari, Vignesh. „Evaluating spreadability of metallic powders for powder bed fusion processes“. Thesis, KTH, Materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-283544.
Der volle Inhalt der QuelleAdditiv tillverkning är teknologier som har stor uträckning inom flyg-, rymd och turbin industrier. Delar kan bli tillverkade direkt genom att lagervis addera material på varandra. En nyckelaspekt som är kritisk till kvalitén av den slutgiltiga komponenten är egenskaperna hos pulvret. De allmänna teknikerna för pulverkarakterisering hjälper till att förutspå flytförmågan hos pulver men relaterar ej till dess spridningsförmåga. För att kunna skapa högkvalitativa skikt av metallpulver är det nödvändigt att förstå pulvrets spridningsförmåga inom pulverbädds baserade additiva tillverkningsprocesser. Målet med denna studie var att skapa ett mått för spridningsförmågan genom bild- och massanalys. Ett experimentellt upplägg i labbskala konstruerades för att efterlikna en pulverbädds baserad additiv tillverkningsprocess. Effekten av bladets hastighet och lagrets tjocklek på fem olika pulver studerades genom användandet av de föreslagna mätetalen. De framtagna mätetalen jämfördes sedan med existerande pulver karakteriseringsmetoder såsom FT-4 Rheometer och pulver analys med hjälp av roterande trumma. Slutligen så jämförs flytbarhets parametrarna med spridbarhets mätetalen. Det visar sig att bildanalysen är tillräckligt bra på att förutspå spridningsförmågan hos pulvret när processparametrarna låtes vara varierande. Mer specifikt så var förhållandet mellan pulvrets yta och det konvexa höljet stort för pulver som visar bra spridning. De framtagna procent värden från massanalysdiagrammen fluktuerar vid olika processparametrar hos de olika pulvren, vilket kan betyda att massanalys kan vara ett potentiellt sätt för att mätta spridningsförmågan hos pulver. Det är förväntat att dessa föreslagna mätetal kommer vara början för utveckling av ytterligare karakteriseringstekniker. Till exempel, för att studera densiteten och tjockleken hos ett lager skulle man kunna skapa homogena lager. Vi förutser att dessa mätetal kommer att bli använda för att skapa standardiseringstekniker för att definiera och kvantifiera spridningsförmågan hos ett pulver och genom detta förbättra kvaliteten av den additiva tillverkningsprocessen.
Jönsson, David, und Mir Kevci. „Geometrical accuracy of metallic objects produced with Additive or Subtractive Manufacturing: a comparative in-vitro study“. Thesis, Malmö högskola, Odontologiska fakulteten (OD), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-19934.
Der volle Inhalt der QuellePurpose: To evaluate the production tolerance of objects produced by additive manufacturing systems (AM) for usage in dentistry and to compare with subtractive manufacturing system (SM) through reverse engineering. Materials and methods: Ten specimens of two geometrical objects were produced by five different AM machines and one SM machine. Object A mimics an inlay-shaped object, meanwhile object B reflects a four-unit bridge model. All the objects were divided into different measuring-axis; X, Y and Z. Measurements were performed with validated and calibrated equipment. Linear distances were measured with a digital calliper while corner radius and angle were measured with a digital microscope. Results: None of the additive manufacturing or subtractive manufacturing groups presented a perfect match to the CAD-file regarding all parameters included in present study. Considering linear measurements, the standard deviation for subtractive manufacturing group were consistent in all axis, except for X- and Y-axis in object A and Y-axis for object B. Meanwhile additive manufacturing groups had a consistent standard deviation in X- and Y- axis but not in Z-axis. Regarding corner radius measurements, SM group overall had the best accuracy for both object A and B comparing to AM groups. Conclusion: Within the limitations of this in vitro study, results support the hypothesis, considering AM had preferable capability to re-create complex and small geometry compare to SM. Meanwhile, SM were superior producing simple geometry and linear distances. Further studies are required to confirm these results.
Sjöström, Julia. „Linkage of Macro- and Micro-scale Modelling Tools for Additive Manufacturing“. Thesis, KTH, Materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-283603.
Der volle Inhalt der Quelledditiva tillverkningsmetoder för stål tävlar mot kommersiell produktion i en ökande takt. Geometrifriheten tillsammans med hög styrka och slagseghet på grund av extrema kylhastigheter gör den här metoden intressant att använda för högpresterande komponenter. De önskvärda materialegenskaperna härstammar från den ultrafina mikrostrukturen. Processen följs ofta av en värmebehandlande härdning för att inducera utskiljningar av andra faser. Printing processen innebär dock flertalet utmaningar som exempelvis sprickbildning, porer, inneslutningar, restspänningar och förvrängningar. Det är därför intressant och viktigt att förutspå egenskaper såsom temperaturutveckling och restspänningar av den slutgiltiga komponenten för att minska tidskrävande ”trial-and-error” och onödigt materialsvin. För att länka ihop olika delar och längdskalor av processen kan ”the integrated computational materials engineering” strukturen användas där länkverktyg kopplar ihop resultat av olika längdskalor. 18Ni300 maraging stål är ett material som har använts till additivt tillverkade produkter i hög utsträckning men det finns fortfarande mycket utrymme för optimering av processen och egenskaperna. I den här avhandlingen, den ”integrated computational materials engineering” inspirerade tillvägagångssättet används för att länka processen med mikrostrukturen, vilken bestämmer egenskaperna. Temperaturutveckling påverkar kraftigt materialegenskaper, restspänningar och deformation vid additiv tillverkning. Förutsägelse av temperatur för ett selektivt lasersmält 18Ni300 stål har därför genomförts i Simufact Additive och länkats med mikrostruktursförutsägande redskapen Thermo-Calc och DICTRA. Olika maskinparametrar har undersökts och efterföljande temperaturer, kylhastigheter, segregeringar och martensitiska starttemperaturer jämförts för olika delar av geometrin. Tilläggningsvis var även restspänningar och deformationer undersökta i Simufact. Det konstaterades att högre energidensitet för lasern orsakade högre temperaturer och kylhastighet vilket generellt skapade mer segregeringar av legeringsämnen och lägre martensitisk starttemperatur i de intercellulära områdena. Det är däremot en gemensam påverkan av kylhastighet och temperatur vilket gör att energidensitet inte är den enskilda bestämmande parametern över segregeringarna. Genom att sänka temperaturen på basplattan uppnåddes lägre temperaturer under den martensitiska starttemperaturen vilket förenklar den martensistiska omvandlingen. Beräkningar av primär dendritisk armlängd användes för att validera kylhastigheterna. Cellstorleken överensstämde bra med litteraturen på <1 μm. Deformationer och restspänningar var väldigt små. Kalibreringarna baserades på litteraturvärden och kräver experimentella värden för att valideras. Den integrerade strukturen som demonstreras i den här avhandlingen förser en insikt i de förväntade egenskaperna av en additivt tillverkad del vilket kan minska och ersätta ”trial-and-error” metoder.
Corona, Galvan Luis. „Prototypage rapide de pièces en acier : étude du dépôt de matière et d'énergie lors de la fusion à l'arc d'un fil par le procédé MIG-CMT“. Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS062/document.
Der volle Inhalt der QuelleA test bench specially dedicated to additive manufacturing by a new technology based on the electric arc melting of a metallic wire has been developed. This technology uses an electric arc welding process called Cold Metal Transfer (CMT) as energy source to ensure the controlled melting of the wire and the deposition of liquid metal droplets to produce mechanical parts by superposing weld beads. The developed technology was used to make specimens from a low alloyed steel wire. The influence of the many parameters controlling the arc welding source on the mechanism of wire melting and transfer of molten metal droplets to form weld beads was studied. The melting-transfer cycles of liquid metal were analyzed in particular with special interest in the energies generated during each of the cycle phases. This knowledge has made possible to find different process settings for increasing the metal deposition rate compared to the pre-recorded standard settings in the microprocessor of the CMT welding generator. Walls consisting of the superposition of a large number of weld beads were then made, and the influence of the addition of many layers on the geometry of the deposits were discussed. Finally, a method of online control of the process, based on the principle of control charts, has been developed. A detailed study of the representative waveforms of current and voltage of the melting / transfer cycle with the CMT process has allowed to identify the most relevant characteristics for detecting, from a control chart, a deviation on the process that may lead to the appearance of geometrical defects
Boissier, Mathilde. „Coupling structural optimization and trajectory optimization methods in additive manufacturing“. Thesis, Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAX084.
Der volle Inhalt der QuelleThis work investigates path planning optimization for powder bed fusion additive manufacturing processes, and relates them to the design of the built part. The state of the art mainly studies trajectories based on existing patterns and, besides their mechanical evaluation, their relevance has not been related to the object’s shape. We propose in this work a systematic approach to optimize the path without any a priori restriction. The typical optimization problem is to melt the desired structure, without over-heating (to avoid thermally induced residual stresses) and possibly with a minimal path length. The state equation is the heat equation with a source term depending on the scanning path. Two physical 2-d models are proposed, involving temperature constraint: a transient and a steady state one (in which time dependence is removed). Based on shape optimization for the steady state model and control for the transient model, path optimization algorithms are developed. Numerical results are then performed allowing a critical assessment of the choices we made. To increase the path design freedom, we modify the steady state algorithm to introduce path splits. Two methods are compared. In the first one, the source power is added to the optimization variables and an algorithm mixing relaxation-penalization techniques and the control of the total variation is set. In a second method, notion of topological derivative are applied to the path to cleverly remove and add pieces. eventually, in the steady state, we conduct a concurrent optimization of the part’s shape and of the scanning path. This multiphysics optimization problem raises perspectives gathering direct applications and future generalizations
Hernandez, Ludwing A. „Integration of Ultrasonic Consolidation and Direct-Write to Fabricate an Embedded Electrical System Within a Metallic Enclosure“. DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/780.
Der volle Inhalt der QuelleCarlsson, Rebecca. „Comparison of turning blades produced by a conventional- and additive manufacturing method“. Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-69032.
Der volle Inhalt der QuelleSamarjy, Ramiz Saeed Matti. „Interaction mechanisms for a laser-induced metallic boiling front“. Doctoral thesis, Luleå tekniska universitet, Produkt- och produktionsutveckling, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-65281.
Der volle Inhalt der QuelleMyers, Kyle M. „Structure-Property Relationship of Binder Jetted Fused Silica Preforms to Manufacture Ceramic-Metallic Interpenetrating Phase Composites“. Youngstown State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1464089607.
Der volle Inhalt der QuelleXu, Jinghao. „Alloy Design and Characterization of γ′ Strengthened Nickel-based Superalloys for Additive Manufacturing“. Licentiate thesis, Linköpings universitet, Konstruktionsmaterial, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-173042.
Der volle Inhalt der QuelleAdditional funding agencies: Agora Materiae Graduate School for multidisiplinary PhD students at Linköping University, and Stiftelsen Axel Hultgren.
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.
Der volle Inhalt der QuelleBeiker, Kair Alexandros, und Konstantinos Sofos. „Additive Manufacturing and Production of Metallic Parts in Automotive Industry : A Case Study on Technical, Economic and Environmental Sustainability Aspects“. Thesis, KTH, Industriell produktion, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-149669.
Der volle Inhalt der QuelleAdditive Manufacturing (AM) består av en familj av olika teknologier som bygger upp komponenter genom att lägga till material lager efter lager ett lager i taget baserat på en digital 3D solid modell. Efter trettio år av utveckling, har AM blivit en mainstream tillverkningsprocess med fler material och nya teknologier involverade i denna process. Utan tvekan har den mest dramatiska och utmanande utvecklingen inom denna grupp av teknologier varit tryckningen av metaller. Nuförtiden fortsätter användningen av AM för tillverkning av delar till slutprodukter att växa. Företag runtom i världen använder tekniken framgångsrikt för produktionen av färdiga varor. AM tillåter designoptimering och tillverkar kundanpassade delar on-demand med nästan samma materialegenskaper som konventionellt tillverkade delar. Det behövs inte användning av kylmedel, fixturer, skärverktyg och andra källor. Fördelarna med AM jämfört med konventionell tillverkning kan förändra den industriella världen och leda till en ny industriell revolution. Efter att mestadels ha gått igenom de olika tekniker och material som används i metallisk AM, beskrivs i denna forskning applikationen av dem i en komponent av motorn till en personbil. En kritikalitet analys görs för att bestämma vilken AM utveckling av de delar som utgör den slutgiltiga produkten som är viktigast för effektiviteten av den totala produktionen. Baserat på denna utveckling utförs en hållbarhetsanalys som består av en analys av miljöpåverkan, produktionskostnad och de samhälleliga effekterna. Men det som har härletts från analysen är att trots den lägre miljöpåverkan i jämförelse med gjutning som en konventionell metod för formning av metaller, är AM kostsamt för produktionen av ett fåtal industriella produkter och dess samhälleliga effekter behöver studeras ytterligare. I själva verket beror kostnaden på produktionsvolymen, satsstorleken samt det höga priset på materialpulvren och byggnadstakten av maskinerna. I framtiden, med mer avancerade maskiner och billigare material kommer kostnaden för metallisk AM att sjunka dramatiskt. Trots alla utveckling, är applikationen av metallisk AM fortfarande inte utbredd. Eftersom materialen samt dess teknik fortfarande är under utveckling förutses en bättre och mer lovande framtid för metallisk AM. Nyckelord: Additive Manufacturing, Direct Digital Manufacturing, massproduktion, bilindustrin, förbränningsmotor, Turbocharger, utveckling, hållbarhetsanalys, livscykelanalys.
Harris, Jonathan Andrew. „Additively manufactured metallic cellular materials for blast and impact mitigation“. Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/271771.
Der volle Inhalt der QuelleCaputo, Matthew P. „4-Dimensional Printing and Characterization of Net-Shaped Porous Parts Made from Magnetic Ni-Mn-Ga Shape Memory Alloy Powders“. Youngstown State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1525436335401265.
Der volle Inhalt der QuelleHopkins, Christopher David. „Development and Characterization of Optimum Process Parameters for Metallic Composites made by Ultrasonic Consolidation“. The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1275414900.
Der volle Inhalt der QuelleStańczak, Magda. „Behaviour of additively manufactured metallic structures under blast loading“. Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0073.
Der volle Inhalt der QuelleThe additive manufacturing technique allows for studies of metallic structures with complex geometry at a laboratory scale. The application of novel structures can be especially beneficial for improving the capacity of energy absorption and blast mitigation. In the presented thesis, the role of the topology of additively manufactured AlSi10Mg aluminum structures of several exemplary cellular structures (i.e., honeycomb, auxetic, lattice, and foam) is studied at static and blast compression. Furthermore, the relationship between the relative density and the deformationresponses of the structures, as well as the energy absorption capacities is analyzed. To investigate the influence of the manufacturing process conditions on the mechanical properties, the material behavior of the printed AlSi10Mg aluminum alloy is studied. For completeness, an analysis of the deformed microstructure is also conducted. The obtained results prove the complexity of the material behavior. Therefore, a phenomenological model based on the modified Johnson-Cook approach is proposed. The developed model describes the obtained characteristics of the printed alloy with much better accuracy than the classical constitutive function. The finite element simulations conducted in LS-DYNA software are used to investigate the deformation mechanisms of the structures in detail. The results are consistent with the analytical calculations and the experimental observations. The final responses indicate that by selecting the appropriate topological parameters, it is possible to affect the performance of structures significantly and thus to improve their energy absorption properties. The resulting experiments and their modeling show that the discussed material and the manufacturing technology have a promising potential
Chen, Shuai. „Investigation of FEM numerical simulation for the process of metal additive manufacturing in macro scale“. Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEI048/document.
Der volle Inhalt der QuelleAdditive manufacturing (AM) has become a new option for the fabrication of metallic parts in industry. However, there are still some limitations for this application, especially the unfavourable final shape and undesired macroscopic properties of metallic parts built in AM systems. The distortion or crack due to the residual stress of these parts leads usually to severe problems for some kinds of metal AM technology. In an AM system, the final quality of a metallic part depends on many process parameters, which are normally optimized by a series of experiments on AM machines. In order to reduce the considerable time consumption and financial expense of AM experiments, the numerical simulation dedicated to AM process is a prospective alternative for metallic part fabricated by additive manufacturing. Because of the multi-scale character in AM process and the complex geometrical structures of parts, most of the academic researches in AM simulation concentrated on the microscopic melting pool. Consequently, the macroscopic simulation for the AM process of a metallic part becomes a current focus in this domain. In this thesis, we first study the pre-processing of AM simulation on Finite Element Method (FEM). The process of additive manufacturing is a multi-physics problem of coupled fields (thermal, mechanical, and metallurgical fields). The macroscopic simulation is conducted in two different levels with some special pre-processing work. For the layer level, the reconstruction of 3D model is conducted from the scan path file of AM machine, based on the inverse manipulation of offsetting-clipping algorithm. For the part level, the 3D model from CAD is reconstructed into a voxel-based mesh, which is convenient for a part with complex geometry. The residual stress of a part is analysed under different preheat temperatures and different process parameters. These simulations imply the potential technique of reducing residual stress by the optimisation of process parameters, instead of the traditional way by increasing preheat temperature. Based on the FEM simulation platform above, two simulations at line level are also studied in this thesis, aiming at the relation between the AM process and part's final quality. These examples demonstrate the feasibility of using macroscopic simulations to improve the quality control during the AM process. In the first task, dataset of heating parameters and residual stress are generated by AM simulation. The correlation between them is studied by using some regression algorithm, such as artificial neural network. In the second task, a PID controller for power-temperature feedback loop is integrated into AM process simulation and the PID auto-tuning is numerically investigated instead of using AM machine. Both of the two tasks show the important role of AM macroscopic process simulation, which may replace or combine with the numerous trial and error of experiments in metal additive manufacturing
Sarentica, Atilla. „Conventional heat treatment of additively manufactured AlSi10Mg“. Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-75056.
Der volle Inhalt der QuelleZhong, Yuan. „Sub-grain structure in additive manufactured stainless steel 316L“. Doctoral thesis, Stockholms universitet, Institutionen för material- och miljökemi (MMK), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-144519.
Der volle Inhalt der QuelleAt the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: Manuscript. Paper 5: Manuscript.
Strand, Emil, und Alexander Wärnheim. „A study of micro- and surface structures of additive manufactured selective laser melted nickel based superalloys“. Thesis, KTH, Materialvetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-188154.
Der volle Inhalt der QuelleGomez, Ortega Arturo. „Prototypage rapide de pièces en alliage d’aluminium : étude du dépôt de matière et d’énergie lors de la fusion à l’arc d’un fil par le procédé MIG-CMT“. Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS067/document.
Der volle Inhalt der QuelleA new additive manufacturing process for metallic parts, based on the arc welding process known as CMT (Cold Metal Transfer), is studied with the objective of building parts with the aluminium alloy Al5Si. A workbench for additive manufacturing based on the 3D printers open-source principle, on which the CMT generator was integrated, was specially developed. The CMT process allows to control the aluminium wire melting and its deposition under the form of droplets on the building surface, forming, after solidification, beads that can be superposed for the parts construction. The process parameters influence on the material transfer and heat transfer during the metal melting and deposition on the build surface, as well as on the geometric characteristics of the deposed beads, in the case of mono-layer deposits, and in the case of multi-layer walls, is studied. Many geometric defects were observed, and their apparition conditions analysed, thanks in particular to the use of a high-speed camera. The understanding of the relations between the process parameters, the melting and heat transfer mechanisms, and the beads geometry, allowed the defects correction by identifying and modifying the process parameters responsible of their apparition. Finally, an on-line control method for the process, based on the analysis of the voltage and current signals produced by the welding generator during the deposition phenomena, making possible the early detection of defects, and then the modification of the process parameters before they are amplified, has been proposed
Ratsimba, Alice. „Élaboration d’objets en cuivre par fabrication additive par extrusion de matière : Etude de la faisabilité : cas de pâtes chargées utilisant des hydrogels de polysaccarides comme systèmes liants“. Electronic Thesis or Diss., Bordeaux, 2024. http://www.theses.fr/2024BORD0054.
Der volle Inhalt der QuelleAmong the seven additive manufacturing methods applied to metals, Extrusion Additive Manufacturing (EAM) appears as a promising technique to produce copper objects. This indirect forming process involves conveying a material and pushing it through an orifice to form strands of material. Three-dimensional objects are built by stacking successive layers from a mixture of metal powder particles and a binding system.Typical formulations for this process include a thermoplastic binder, and the materials are usually packaged in filament form, which is complex to handle and convey. In addition, post-processing steps are usually lengthy and require specific equipment, which can lead to high costs and production lead times.In this perspective, the use of formulations using biobased binder systems appears to be a promising alternative, offering potential advantages in terms of production speed, energy efficiency and environmental impact. The considered materials are metal pastes based on polysaccharide hydrogels loaded with copper powder. The main objective of this work is to study the suitability of the behaviour of these formulations with the extrusion additive manufacturing process. Defining printability criteria helps to understand relationships between the properties of the formulations, the course of the shaping process, and the quality of the obtained objects
Engblom, Eyvind. „Effect of oxygen concentration in build chamber during laser metal deposition of Ti-64 wire“. Thesis, KTH, Materialvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-230638.
Der volle Inhalt der QuelleSandell, Viktor. „Defects in E-PBF Ti-6Al-4V and their Effect on Fatigue Behaviour : Characteristics, Distribution and Impact on Life“. Licentiate thesis, Luleå tekniska universitet, Materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-81155.
Der volle Inhalt der QuelleSUDDEN
Masmoudi, Amal. „Modélisation et développement expérimental du procédé de fabrication additive par fusion laser sélective d'un lit de poudre métallique : influence de la pression de l'atmosphère“. Thesis, Belfort-Montbéliard, 2016. http://www.theses.fr/2016BELF0287/document.
Der volle Inhalt der QuelleThe selective laser melting process (SLM) of a metallic powder bed is an innovative process that allows the manufacturing of complex shape parts directly from a CAD file via a complete melting of powder layers deposited successively. During the SLM process, the high laser energy density creates many thermal cycles: melting - vaporization - solidification.The purpose of this work was: 1) to better characterize and understand experimentally the phenomena that occur during the laser beam - powder / molten metal pool interaction and 2) to develop a numerical model taking into account the phenomena of melting and vaporizing of the material and the presence of the surrounding gas in the build chamber.In a first time, considering simple geometries (tracks and surfaces) and 316L stainless steel as material, we studied the interaction between the laser beam, the powder bed and the liquid metal pool using several experimental techniques (spectrometry, calorimetry, ...) in order to understand the nature and the role of the metal vapor generated during the process. The results showed that the vapor has no effect on the transmission of the laser beam energy to the material during the SLM process. Meanwhile it leads to the deposition of condensed vapor and also drag some molten metal droplets.In a second time a numerical model was developed to determine the influence of the pressure of the surrounding environment on the melting process of a powder bed by a laser beam. Parameters characterizing the evolution of the physical properties of the material and of the gaseous medium according to the temperature and pressure were incorporated into the model database. Some material parameters were determined from the literature and others were obtained empirically using specific experimental measurements.Finally, this numerical model, complementing experimental results, was used to treat the main subject of the thesis which is the effect of the surrounding pressure on the SLM process. The model helped to clarify the physical phenomena provided by the change in the pressure level and its validity was checked through experimental measurements
Eriksson, Philip. „Evaluation of mechanical and microstructural properties for laser powder-bed fusion 316L“. Thesis, Uppsala universitet, Tillämpad materialvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-355882.
Der volle Inhalt der QuelleVillaret, Flore. „Développement d’une jonction austéno-martensitique à gradient de composition chimique par fabrication additive“. Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI104.
Der volle Inhalt der QuelleThis PhD work concerns the problem of bimetallic austenitic/martensitic steel connections. This research action focuses on a 316L austenitic steel (X2 CrNiMo 18-12-02) / Fe-9Cr-1Mo (X10 CrMo 9-1) martensitic steel connection. The objective is to understand the metallurgical problems related to the assembly of these two steels and to evaluate the possibilities of using powder metallurgy and additive manufacturing to produce austenitic/martensitic steel transitions. A weld obtained by electron beam is used as a reference for this study which focuses on the interest of powder metallurgy to achieve a transition between two steels. Materials with a chemical composition gradient have been consolidated by HIP and SPS and show very good mechanical properties and an excellent junction between the two steels. By additive manufacturing (DED-LB or PBF-LB), we also obtain very good bonds between the two steels, but the microstructures are much more complex. Curiously, we observe that the higher the cooling rate, the higher the ferrite fraction in the martensitic steel. Different calculations based on the nucleation and growth of the austenitic phase have made it possible to propose a coherent scenario to explain the phase fractions present in the materials. The transition zone between the two steels shows strong variations in hardness. These variations are explained by changes in chemical composition, leading to modifications in phase change temperatures, and the particular thermal cycles seen during building. From a technological point of view, materials obtained by additive manufacturing have tensile performances very similar to those obtained by electron beam welding. It is shown that additive manufacturing also makes it possible to control the composition gradient between a martensitic and an austenitic steel
Jain, Akshay Ashok. „Design and LENS® Fabrication of Bi-metallic Cu-H13 Tooling for Die Casting“. The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1385987045.
Der volle Inhalt der QuelleHahne, William. „Optimization of laser powder bed fusion process parameters for 316L stainless steel“. Thesis, Uppsala universitet, Oorganisk kemi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-448263.
Der volle Inhalt der QuelleWahman, Clarence. „Corrosion of additively manufactured magnesium alloy WE43 : An investigation in microstructure and corrosion properties of as built samples manufactured with Powder Bed Fusion-Laser Beam“. Thesis, Uppsala universitet, Tillämpad materialvetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-448525.
Der volle Inhalt der QuellePapavassiliou, Alessandro. „Analisi bibliografica e di mercato delle polveri metalliche utilizzabili in processi additivi“. Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
Den vollen Inhalt der Quelle findenPepić, Sanjin, und Otto Ridemar. „Experimental and Theoretical Investigation of Selective Laser Melted Uddeholm Dievar ®“. Thesis, KTH, Materialvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254247.
Der volle Inhalt der QuelleDet huvudsakliga problemet som denna avhandling behandlar är bristen på forskning och kunskap inom selective laser melting (SLM) 3D-printing med Uddeholm Dievar®. Avsaknaden kan leda till sämre kvalité och produktegenskaper hos legeringen. Det kan även leda till ovisshet gällande val av lämplig värmebehandling. Arbetet fokuserar på att dokumentera utformningen av stålets mikrostruktur när Uddeholm Dievar® tillverkas med den additiva tillverkningsmetoden SLM. Tillverkningsprocessen består av en högeffektslaser som detaljerat smälter samman tunna lager pulver, ett lager i taget, tills att en tredimensionell produkt skapats utefter valda ritningar. Använda metoder är; utförandet av en teoretisk studie, vetenskapliga experiment och thermodynamiska beräkningar. Analys av mikrostrukturen genomförs med hjälp av svepelektronmikroskåp där teknikerna Energy-dispersive X-ray spectroscopy (EDS) och Electron backscatter diffraction (EBSD) används. Syftet med EDS är att kartlägga de ingående elementen i legeringen, syftet med EBSD är att se orientering av de kristallografiska faserna i atomgittret. Resultaten visar på att legeringen, både före och efter printing, till största del består av martensit med en låg mängd restaustenit. Mängden primärkarbider är relativt låg och har klassifiserats som typen MC (V-rik) och/eller M6C (Mo- rik). Den kvarstående restausteniten kan möjligen förklaras av segringen av ingående legeringsämnen där kolhalten är en dominerande faktor som sänker MS-temperaturen. Detta gör att restaustenit förekommer trots den höga kylhastigheten som varierar mellan 103 och 108 [K/s] i SLM.
Balzi, Davide. „Esecuzione di micrografie su provini in acciaio inossidabile PH1 realizzati per additive manufacturing“. Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
Den vollen Inhalt der Quelle findenPastuschka, Lisa, und Peter Appel. „Additive Fertigung von Metallen – Einsatz des LaserCUSING®s im Bereich Automotive“. Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-215075.
Der volle Inhalt der QuelleVandi, Daniele. „Studio del comportamento a fatica di provini in Maraging steel realizzati tramite Additive Manufacturing“. Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
Den vollen Inhalt der Quelle findenStåhl, Dennis, und Siyu Guo. „Innovation genom additiv tillverkning“. Thesis, KTH, Maskinkonstruktion (Inst.), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-230585.
Der volle Inhalt der QuelleAdditive manufacturing, AM, is a technique that is developing in an incredible pace. Conventional manufacturing methods, like lathe turning or casting for instance, are limited when it comes to creating products with complex geometries, in these cases AM is a good complement. Previously though, material characteristics like tensile strength and yield point is something that AM has been compensating with. But in the current rate of development, the AM-technique can soon replace most conventional manufacturing methods completely. The purpose of this project is to describe the possibilities in AM today and what could be expected in the future.Since complex geometries is not a problem with AM, the products can be produced in only one step compared to conventional methods where it often takes several steps to produce a product. AM with metal is something that is developing fast and there are already many different methods, for instance Selective Laser Sintering, Selective Laser Melting, Beam Metal Deposition, Electron Beam Melting and Binder Jetting. These methods use different techniques to create prototypes and they all have their pros and cons what matters cost, strength and working speed.Tools in all forms are examples of products that requires high performance and a long life-span. To integrate the requirement of high performance and the possibilities with complex geometries through AM, a twisted drill with internal cooling channels is produced in this project. The internal cooling channels are shifting in diameter to optimize the inlet of coolant and at the same time increase the outlet.As mentioned earlier there are many different methods for AM in metal. The method that is considered the best for this purpose is Selective Laser Melting since this method creates compact metal products with high strength. A 3D-model of the twisted drill was created in Solid Edge ST9 and was then analyzed in ANSYS Workbench to see the impact of the internal cooling channels during use of the drill. The results show that the total deformation is 0,68μm and maximum tension is 33,95MPa, both in the middle of the drill. Neither the total deformation or the maximum tension reaches a critical limit and therefor the drawn conclusion is that this model would reach the requirements given to a drill.The development of new methods in AM with metal is going fast and in a near future the new techniques will have increased in working speed so much and be price effective enough to replace most of the conventional manufacturing methods completely.
Tamburrini, Simone. „Produzione e caratterizzazione di componenti in WC-Co mediante selective laser melting“. Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
Den vollen Inhalt der Quelle findenBorsari, Mattia. „Studio di strutture reticolari metalliche stampate con tecnologia additiva a letto di polvere e analisi del comportamento a fatica tramite DIC (Digital Image Correlation)“. Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
Den vollen Inhalt der Quelle findenConti, Alfredo. „Tecniche della manifattura additiva - applicazioni in ambito aeronautico e aerospaziale“. Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13306/.
Der volle Inhalt der QuelleZanini, Filippo. „X-ray computed tomography for coordinate metrology and industrial applications“. Doctoral thesis, Università degli studi di Padova, 2017. http://hdl.handle.net/11577/3425370.
Der volle Inhalt der QuelleLa tomografia computerizzata a raggi-X (CT) si è affermata negli ultimi anni come tecnologia di misura innovativa per la metrologia dimensionale nel settore industriale. L’utilizzo di un sistema CT industriale comporta una serie di importanti vantaggi nei confronti di altri sistemi di misura a coordinate (CMSs). In particolare, il CT consente di ottenere un modello tridimensionale completo dell’oggetto scansionato e di condurre misure non distruttive e non a contatto di geometrie e caratteristiche sia esterne sia interne e di difficile accesso. Tuttavia, alcuni svantaggi rilevanti limitano una più estesa diffusione di questa tecnologia nel settore industriale. Uno dei problemi più critici risiede nella riferibilità metrologica delle misure CT, complicata dalla difficoltà nel determinare l’incertezza di misura e nel valutare le prestazioni metrologiche dei sistemi CT. Inoltre, uno standard internazionale dedicato ai test per l’accettazione e per la verifica delle prestazioni dei sistemi CT è tuttora in via di sviluppo. Le attività sperimentali presentate in questo lavoro di tesi sono state focalizzate principalmente sulla valutazione e sul miglioramento delle prestazioni metrologiche del CT. L’influenza del materiale sugli errori di misura di lunghezza è stata studiata mediante indagini basate su due campioni di riferimento: una hole plate di alluminio, caratterizzata da un’influenza significativa del materiale e una ball plate di rubino, caratterizzata da un’influenza del materiale trascurabile. I risultati ottenuti hanno contribuito alla campagna sperimentale incentrata su questo argomento organizzata dal working group dedicato allo sviluppo del futuro standard ISO per il CT. La qualità d’immagine delle proiezioni radiografiche bidimensionali acquisite mediante CT è fondamentale per ottenere una buona qualità nella ricostruzione del modello tridimensionale dell’oggetto scansionato. Essa è connessa al concetto di blurring o sfocatura dell’immagine e, di conseguenza, alla qualità della macchia focale da cui viene emesso il fascio di raggi X. All’interno di questa tesi vengono descritti nuovi metodi sviluppati per valutare l’effettiva dimensione della macchia focale e l’eventuale drift che essa può subire durante una scansione tomografica. Considerando l’intera procedura di misura CT, una caratteristica metrologica molto importante da considerare è la risoluzione strutturale metrologica (MSR). Nonostante siano stati proposti diversi metodi per la valutazione della MSR, un test univoco da includere nel futuro standard ISO dedicato al CT deve ancora essere definito. In questa tesi, il metodo ‘Hourglass’ – sviluppato dall’Università di Padova - è stato selezionato per valutare la MSR. Questo metodo è stato migliorato mediante la misura di un elevato numero di distanze e applicando una definizione di MSR simile a quella proposta dalla linea guida tedesca VDI/VDE 2617-13. Inoltre, il concetto alla base di tale metodo è stato confrontato con quello di altri metodi e i principali fattori che possono influenzarne i risultati sono stati identificati e valutati. Essendo la tomografia computerizzata a raggi-X una tecnica di misura molto versatile, il suo potenziale può essere sfruttato da un gran numero di applicazioni industriali. Tuttavia, l’accuratezza dei risultati di misura CT è spesso ignota. Per questa ragione, la determinazione dell’accuratezza di misura e il confronto con altri metodi di misura consolidati sono cruciali per una piena accettazione del CT in ambito industriale. In questa tesi sono stati affrontati due casi di rilevanza industriale: (i) analisi di porosità su componenti metallici realizzati mediante produzione additiva e (ii) determinazione dell’usura di componenti protesiche in polietilene. Per quanto riguarda il primo studio, il CT è stato confrontato con altre tecniche d’indagine: metodo di Archimede, picnometro a gas e analisi microscopica di sezioni di taglio. In aggiunta, una macchina di misura a coordinate (CMM) multi-sensore è stata utilizzata per ottenere valori di riferimento per l’area di un certo numero di pori distribuiti su alcune sezioni di taglio selezionate. Nel secondo studio, il metodo CT proposto è stato validato mediante confronto con il metodo gravimetrico, che è l’attuale metodo di riferimento utilizzato per la determinazione del grado di usura.
Säger, Florian. „A Feasibility Study of an Automated Repair Process using Laser Metal Deposition (LMD) with a Machine Integrated Component Measuring Solutio“. Thesis, KTH, Industriell produktion, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-248022.
Der volle Inhalt der QuelleTillverkare har börjat se stora möjligheter i att reparera slitna eller skadade komponenter som ett sätt att spara resurser, så som råmaterial och energi. Med den besparingen minskar kostnaderna och vinsten kan således maximeras. Reparation möjliggör även återanvändning av komponenter, vilket förlänger komponentens livslängd och leder till förbättrade hållbarhetsåtgärder. Dock tillämpas reparation inte i någon stor utsträckning i nuläget, främst eftersom kostnaderna för reparation överstiger kostnaderna för att köpa en ny komponent. En av de största kostnaderna för att reparera en metallkomponent är att identifiera och kvantifiera slitna eller skadade områden med hjälp av olika externa mätsystem, som är en väldigt arbetsintensiv process. En automatiserad mätprocess skulle minska avsökningskostnaden avsevärt och således reducera den totala kostnaden för komponenten. För att möjliggöra en automatiserad reparationsprocess i en enda maskinlösning är det en förutsättning att en mätanordning ingår i maskinhöljet. Därför har olika mätningslösningar utvärderats med avseende på användbarhet i "TRUMPF TruLaser Cell 3000 Series", vilket är en maskin som använder Laser Metall Deposition-teknik (LMD-teknik) för att skriva ut och svetsa metall på en definierad yta. En teoretisk analys av olika lösningar har utförts, där den teoretiskt mest lämpliga lösningen validerades genom att appliceras till maskinen. Valideringen genererade en modell av ytan av en testkomponent. Sedan utfördes en automatiserad, målrelaterad jämförelse med ett specialiserat CAM-program baserat på modellresultatet, för att bestämma möjligheten att upptäcka slitna områden. Genom att verifiera förmågan att upptäcka slitna områden samt genomförandet av en lyckad reparation kan grunden för en helt automatiserad reparationsprocess bevisas som möjlig i en enda maskinlösning.
Das reparieren von abgenutzten oder beschädigten Komponenten wird immer attraktiver für Hersteller. Es ermöglicht es Ressourcen einzusparen wie beispielsweise Rohmaterial und Energie, was die Lebenszeit einer Komponente verlängert und damit die Nachhaltigkeit verbessert. Allerdings ist Reparieren nach wie vor nicht weit verbreitet, hauptsächlich dadurch bedingt, dass die Reparaturkosten die Kosten für eine neue Komponente übersteigen. Einer der größten Kostenfaktoren des reparieren einer Metallkomponente ist der Arbeitsintensive Teil der Identifizierung und Quantifizierung des abgenutzten oder beschädigten Bereichs mit verschiedensten externen Vermessung Systemen. Ein automatisierter Vermessungsprozess würde die Kosten signifikant reduzieren und neue Applikationen ermöglichen. Das automatisieren der gesamte Prozesskette – in einer Single-Maschinenlösung – erfordert, dass eine Messeinrichtung im Bearbeitungsraum der Maschine angebracht wird. Dafür werden verschiedene Lösungen nach Anwendbarkeit an der Trumpf Laser Cell 3000 Serie hin beurteilt. Eine Maschine, welche Laser Metal Deposition (LMD) als Technologie anwendet um Material auf Oberflächen aufzubringen. Nach einer theoretischen Analyse verschiedener Lösungen wird die beste Lösung va durch anbringen an die Maschine validiert. Bei der Validierung wird ein Oberflächenmodel erzeugt. Das Ergebnis wird dann genutzt um die Fähigkeit zu belegen, dass beschädigte Stellen, durch einen Soll-Ist-Vergleich in einem speziellen CAM Programm, automatisch detektiert werden können. Basierend auf diesem Beleg und mit dem Ergebnis eine Komponente erfolgreich reparieren zu können, gilt die These eines automatisierten Reparaturprozesses in einer Single-Maschinenlösung als beweisen.
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.
Der volle Inhalt der QuelleCosta, 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.
Der volle Inhalt der QuelleLin, Yan-Ji, und 林延輯. „Fe-based metallic glass powder preparation and additive manufacturing workpiece properties analysis“. Thesis, 2017. http://ndltd.ncl.edu.tw/handle/26856326799082501680.
Der volle Inhalt der Quelle國立中央大學
材料科學與工程研究所
105
The alloy composition of Fe-Cr-Mo-C-B-Y-Co 7 components Fe-based alloy was selected as the master alloy and prepared by vacuum induction melting. Then the alloy ingots were re-melted and fabricated into spherical alloy powder by inert gas atomization process in the Material and Chemical Laboratories, Industrial Technology Research Institute (ITRI, Hsinchu). After size sieving, XRD analysis, and SEM examination, the atomized powders which can meet the specification of additive manufacturing were collected to do the linear laser melting test and cube selective laser melting (SLM) test. Hopefully, the optimum process parameters of SLM that is suitable for additive manufacturing can be designed. After size sieving, the particle size of the most amount powder locates around 37~44 μm. According to the XRD results, all the powders which particle size below 63 μm are confirmed to be amorphous. On contrary, the structure of the powders with particle size more than 63 μm was found to contain an amorphous matrix co-existing with a C23C6, crystalline phase. The intensity of the C23C6 peak increases with increasing the powder size. Meanwhile, a spherical or near-spherical appearance can be clearly observed by SEM examination for all powders. 10 sets parameters of laser power and scanning rate were obtained from the results of linear laser melting test by OM observation. Then these 10 sets parameters and an additional parameter (which can successfully apply on produce maraging steel sample) were applied to do the cube SLM test. After SLM, cracks and spalls were found on the side view of most SLM cubes except the cubes made by the parameters of P240-S650 (#7), P240-S700(#8), and the parameter for maraging steel (#11). However, after the SEM examination on the cube samples made by parameters of #7, #8, and #11, respectively, there still can be found several unmelted powder particles on the surface of cube sample which made by the parameters of #8 and #11. In parallel, the laser melted powder layers of the cube sample made by # 11 parameter exhibit an insufficient fusion condition and the separated powder particles still can be seen on the side view of cube sample. Although there are no unmelted powder on the cube surface and no insufficient fusion condition on the side view for the cube sample made by #7 parameter, but there is one crack throughout the whole cube sample. On the other hand, there are only few unmelted powder particles on the sample surface, no clear separation of laser melted powder layers, and no obvious creaking can be found in the cube sample made by #8 parameter. Moreover, the cube sample made by parameter #8 presents higher hardness than the samples made by the parameters of #7 and #11, which means that the cube sample made by #8 parameter possesses higher product density than the other. In summary, #8 parameter seems the optimum process condition in this study and can be applied as the reference for the further laser additive manufacturing the Fe-based amorphous alloy. Keyword: Fe-based metallic glass, atomization process, additive manufacture
Oliveira, Bernardo Garrett Neuparth Moura de. „Fatigue behaviour of metallic components obtained by topology optimization for additive manufacturing“. Master's thesis, 2019. https://hdl.handle.net/10216/122446.
Der volle Inhalt der Quelle