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Dewidar, Montasser Marasy A. "Direct and indirect laser sintering of metals." Thesis, University of Leeds, 2002. http://etheses.whiterose.ac.uk/3973/.
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Manufacturing functional prototypes and tools using conventional methods usually is a time consuming procedure with multiple steps. The pressure to get products to market faster has resulted in the creation of several Rapid Prototyping (RP) techniques. However, potentially one of the most important areas of Rapid Manufacturing (RM) technology lies in the field of Rapid Tooling (RT). Layer manufacture technologies are gaining increasing attention in the manufacturing sector for the production of polymer mould tooling. Layer manufacture techniques can be used in this potential manufacturing area to produce tooling either indirectly or directly, and powder metal based layer manufacture systems are considered an effective way of producing rapid tooling. Selective Laser Sintering (SLS) is one of available layer manufacture technologies. SLS is a sintering process in which shaped parts are built up layer by layer from bottom to top of powder material. A laser beam scans the powder layer, filling in the outline of each layers CAD-image, and heats the selected powder to fuse it. This work reports the results of an experimental study examining the potential of layer manufacturing processes to deliver production metal tooling for manufacture of polymer components. Characterisation of indirect selective laser sintering and direct selective laser sintering to provide the metal tooling is reported. Three main areas were addressed during the study: mechanical strength, accuracy, and build rate. Overviews of the results from the studies are presented. Two materials (RapidSteel 2.0 and special grade of highspeed steel) and also two generations of SLS machines Sinterstation 2000 and sinterstation research machine, which was constructed in Leeds) were used during this work.
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Olakanmi, Eyitayo Olatunde. "Direct selective laser sintering of aluminium alloy powders." Thesis, University of Leeds, 2008. http://etheses.whiterose.ac.uk/1476/.
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The SLS/SLM of aluminium powder had been investigated by studying the effect of powder properties and laser processing parameters on the microstructures and properties of both single layer and multiple layer builds. On the basis of experimental evidence, the SLS/SLM of aluminium powders could be categorised into full melting (SLM) which was found to have occurred in both pure and pre-alloyed aluminium powders, and binary liquid phase sintering (SLS) which occurred in blended bimodal or trimodal powders. That successful disruption of the oxide film is possible is a significant result, as is the constitutional effect on this. The spheroidisation and oxide disruption phenomena in SLS/SLM processed aluminium powders arc suggested to be mainly controlled by the amount of oxide on the as-received powder's surface, the degree of the uniformity of the distribution of the surface oxide film covering the aluminium particles as well as the nature of thermal mismatch existing between the oxide film and the parent aluminium particle which was dependent on the phase present in the oxide film (alumina, mullite, and spinel). It was discovered that the attainment of high sintered density and desirable microstructural properties in the blended aluminium powders is consequent upon the determination of the right processing conditions, appropriate choice of powders (in terms of particle size distribution, spherical particle shape, and component ratio). Moreover, it is now evident that chemical constitution of the blended aluminium powders only becomes influential in the determination of the properties of SLS processed parts when the choice of processing parameters and powder properties are correct. The choice of powder properties determines the thermal conductivity of the powder bed which in effect controls the sintered properties. This had been inferred from the relationship between powder tapping density on one hand, and selective laser sintered (SLS) density, dendrite spacing and fraction of primary phase on the other hand. In making smaller samples, it has been shown that the attainment of high sintered density (up to 90%) and a good microstructure are feasible. These arc accompanied by reasonable hardness values, comparable to those of cast Al-12wt%Si castings. In fabricating larger sized parts for mechanical testing, defects such as delamination became more noticeable leading to poor mechanical properties in those samples. Thus, it is now clear that physical limitations of the sintering machine hinder the production of SLS/SLM processed parts having excellent structural integrity. On the basis of this work, it is envisaged that the use of pre-alloyed Al-Si powders of uniform composition, but a wider particle size and size distribution, blended to optimise the bed density, offers the potential to produce light alloy components by SLS. In conclusion, the specific laser energy input, the component ratio, and the particle size and size distribution of the powder were found to have strongly influenced the densitication mechanism and the solidification process in a small sized aluminium powdered part fabricatedb y SLS/SLM process.
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Pozzi, Francesco. "Direct metal laser sintering of steel with high vanadium content." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13548/.
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La definizione di "rapid prototyping" è ben nota. Ci si riferisce a quell'insieme di tecnologie utilizzate per la realizzazione di oggetti partendo da modelli geometrici molto complicati, realizzando protitipi direttamente dal disegno CAD 3D. Le tecnologie RP sono state poi sviluppate per l'industria artigianale, nell'obiettivo di accelerare la produzione senza perdita di precisione nella costruzione. Tra queste tecniche sono sorte quelle di selective laser sintering.
La sinterizzazione è il processo termico e meccanico per produrre materiali compattando sostanze in polvere, sotto una certa pressione o temperatura; più precisamente, nella sinterizzazione laser le polveri sono riscaldate per un tempo brevissimo.
La fisica che descrive questo processo è piuttosto articolata, dato che la descrizione parte dall'assorbimento di radiazione laser e che comprenderà conduzione termica nella polvere, trasformazione di fase di un materiale eterogeneo, formazione di fase solida con diversi meccanismi di condensazione e lo sviluppo delle diverse microstrutture dell'acciaio.
Il lavoro sperimentale che è stato svolto è la produzione di una polvere di acciaio e vanadio utilizzabile in solid state sintering, ma dato quanto detto, lo studio ha incluso una descrizione più generale del processo della sinterizzazione metallica da polveri.
Nel corso del lavoro si è contribuito alla messa a punto della stampante 3D per sinterizzazione di polveri metalliche realizzata alla 3d4mec, soffermandosi nella ricerca dei parametri ottimali per la stampa di polvere StainlessSteel CX by EOS.
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Cruz, Fernando Manuel Martins. "Direct manufacture of hydroxyapatite based bone implants using selective laser sintering." Thesis, Bucks New University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408253.
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Taylor, Christopher Martin. "Direct laser sintering of stainless steel : thermal experiments and numerical modelling." Thesis, University of Leeds, 2004. http://etheses.whiterose.ac.uk/378/.
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SLS is a commercial solid freeform fabrication process. Layers of powder material are bonded by a laser beam to rapidly manufacture three dimensional freeform models. In this work, the direct SLS of room temperature single-phase steel powder beds is researched. Two approaches are adopted: - Experimental analysis of heat transfer in the process; - Numerical modelling of the process. Experimental work involves the use of analytical equations to calculate the thermal conductivity and laser energy absorptance of the SLS powder bed. Experiments take place in a range of representative situations. Two temperature measurement systems are used, requiring some custom-designed elements. Conductivity values in the range 0.07 to 0.25 W/(m. K) are found, dependent on atmospheric gas and powder particle size. Absorptance varies from 0.08 to 0.21, dependent on atmosphere and material type. Measurements are made to learn more about temperature variation in the bed with position and time. It is found that processed material melts and solidifies in under 4 seconds in studied cases. Numerical modelling involves developing and testing an existing Fortran model of the SLS process. A method is devised to visualise modelled parts in 3D. Preprocessing is simplified, and more status information is communicated during execution. The effect on modelled parts of changes made to the program are tested. The stability of part depth is improved. The nature of parts is categorised against input parameters. The area, relative density and morphology of manufactured and modelled single layer parts are compared. Manufactured scans are found to have a variable cross-sectional shape, whereas the cross-sectional shape of modelled scans does not change. Modelled parts are found to be significantly smaller than manufactured parts. Reasons for these two differences are suggested.
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Říčan, Daniel. "Návrh výroby tělesa plynového analyzátoru s využitím metody Direct Metal Laser Sintering." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229527.
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This master’s thesis deals with the possibility of manufacturing gas analyzer by Rapid Prototyping Technology and it with the method Direct Metal Laser Sintering. The theoretical part describes the current production of component in the Frentech Aerospace LLC and innovation with the DMSL method in the company Innomia Furthermore JSC. Then an analysis of the principle of single methods Rapid Prototyping, especially the method of Direct Metal Laser Sintering, is implemented. The aim of the experimental part is to compare the mechanical properties and material structures, conventional metallurgy and powder metallurgy. The thesis also contains a technical-economic evaluation comparing the manufacture of mechanical part by conventional and advanced additive technology.
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Chen, Tiebing. "Analysis and modeling of direct selective laser sintering of two-component metal powders." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/5818.
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Thesis (Ph.D.)--University of Missouri-Columbia, 2005.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (November 15, 2006) Vita. Includes bibliographical references.
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Das, Suman. "Direct selective laser sintering of high performance metals : machine design, process development and process control /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
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Xu, Yangzi. "Corrosion Behavior of Direct Metal Laser Sintered Ti-6Al-4V for Orthopedic Applications." Digital WPI, 2017. https://digitalcommons.wpi.edu/etd-dissertations/282.
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Ti-6Al-4V alloy has been used as biomedical implants for decades because of its superior mechanical properties, good biocompatibility, lack of allergic problems and good corrosion resistance. It is widely used as the tibial components in total knee arthroplastry and hip cup in total hip replacement. However, the mechanical properties of Ti-6Al-4V implant can be deteriorated due to corrosion pits. In the past decades, the rapid developments in additive manufacturing have broadened their applications in biomedical area due to the high geometrical freedom in fabricating patient-friendly implants. However, the high-localized thermal input and fast cooling rate during laser processing usually result in non-equilibrium phase with high residual stress. Therefore, it is necessary to apply proper post-treatments on the as-printed parts to ensure better properties. In this work, various post-treatments (e.g. post-heat treatments, hot isostatic pressing) were applied aim to improve the corrosion behavior of direct metal laser sintered Ti-6Al-4V parts. The effect of post-treatment temperature on the mechanical properties and corrosion behavior were examined experimentally. A discussion on factors influencing corrosion rate was presented, and the corrosion mechanism on the Ti-6Al-4V part in simulated body fluid was proposed. Based on the electrochemical measurement results, enhanced corrosion resistance was observed in the samples after high temperature HIPing at the annealing temperature (α+β region) of 799°C.
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Coffy, Kevin. "Microstructure and Chemistry Evaluation of Direct Metal Laser Sintered 15-5 PH Stainless Steel." Master's thesis, University of Central Florida, 2014. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/6256.
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15-5PH stainless steel is an important alloy in the aerospace, chemical, and nuclear industries for its high strength and corrosion resistance at high temperature. Thus, this material is a good candidate for processing development in the direct metal laser sintering (DMLS) branch of additive manufacturing. The chemistry and microstructure of this alloy processed via DMLS was compared to its conventionally cast counterpart through various heat treatments as part of a characterization effort. The investigation utilized optical microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-Ray diffractometry (XRD), energy dispersive X-Ray spectroscopy (EDS) and glow discharge atomic emission spectrometry (GDS) techniques. DMLS processed samples contained a layered microstructure in which the prior austenite grain sizes were relatively smaller than the cast and annealed prior austenite grain size. The largest of the quantifiable DMLS prior austenite grains had an ASTM grain size of approximately 11.5-12 (6.7?m to 5.6?m, respectively) and the cast and annealed prior austenite grain size was approximately 7-7.5 (31.8?m to 26.7?m, respectively), giving insight to the elevated mechanical properties of the DMLS processed alloy. During investigation, significant amounts of retained austenite phase were found in the DMLS processed samples and quantified by XRD analysis. Causes of this phase included high nitrogen content, absorbed during nitrogen gas atomization of the DMLS metal powder and from the DMLS build chamber nitrogen atmosphere. Nitrogen content was quantified by GDS for three samples. DMLS powder produced by nitrogen gas atomization had a nitrogen content of 0.11 wt%. A DMLS processed sample contained 0.08 wt% nitrogen, and a conventionally cast and annealed sample contained only 0.019 wt% nitrogen. In iron based alloys, nitrogen is a significant austenite promoter and reduced the martensite start and finish temperatures, rendering the standard heat treatments for the alloy ineffective in producing full transformation to martensite. Process improvements are proposed along with suggested future research.M.S.M.E.
Masters
Materials Science Engineering
Engineering and Computer Science
Materials Science and Engineering
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Sekerka, Vít. "Výroba dílů technologií DMLS a jejich porovnání s jinými konvenčními technologiemi z hlediska ekonomické náročnosti." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229969.
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This diploma thesis presents a technology based on the gradual smelting of fine layers of metal powder by using a laser beam. It explains and describes basic terminology related to the Rapid Prototyping technology, its division and practical usage. A part of the thesis is also the fabrication of several prototype parts by Direct Metal Laser Sintering including the economical comparison of their fabrication with other conventional technologies.
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De, Beer N., and A. I. Odendaal. "The geometrical accuracy of a custom artificial intervertebral disc implant manufactured using Computed Tomography and Direct Metal Laser Sintering." Journal for New Generation Sciences, Vol 10, Issue 3: Central University of Technology, Free State, Bloemfontein, 2012. http://hdl.handle.net/11462/613.
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Published ArticleRapid Manufacturing (RM) has emerged over the past few years as a potential technology to successfully produce patient-specific implants for maxilla/facial and cranial reconstructive surgeries. However, in the area of spinal implants, customization has not yet come to the forefront and with growing capabilities in both software and manufacturing technologies, these opportunities need to be investigated and developed wherever possible. The possibility of using Computed Tomography (CT) and Rapid Manufacturing (RM) technologies to design and manufacture a customized, patient-specific intervertebral implant, is investigated. Customized implants could aid in the efforts to reduce the risk of implant subsidence, which is a concern with existing standard implants. This article investigates how accurately the geometry of a customized artificial intervertebral disc (CAID) can represent the inverse geometry of a patient's vertebral endplates. The results indicate that the endplates of a customized disc implant can be manufactured to a calculated average error of 0.01mm within a confidence interval of 0.022mm, with 95% confidence, when using Direct Metal Laser Sintering.
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Verma, Anoop P. "Minimizing Build Time and Surface Inaccuracy of Direct Metal Laser Sintered Parts: An Artificial Intelligence Based Optimization Approach." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1249840383.
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Raja, Sandeep. "The systematic development of Direct Write (DW) technology for the fabrication of printed antennas for the aerospace and defence industry." Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/14930.
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Low profile, conformal antennas have considerable advantages for Aerospace and Military platforms where conventional antenna system add weight and drag. Direct Write (DW) technology has been earmarked as a potential method for fabricating low profile antennas directly onto structural components. This thesis determines the key design rules and requirements for DW fabrication of planar antennas. From this, three key areas were investigated: the characterisation of DW ink materials for functionality and durability in harsh environments, localised processing of DW inks and the optimisation of DW conductive ink material properties for antenna fabrication. This study mainly focused on established DW technologies such as micro-nozzle and inkjet printing due to their ability to print on conformal surfaces. From initial characterisation studies it was found that silver based micro-nozzle PTF inks had greater adhesion then silver nano-particle inkjet inks but had lower conductivity (2% bulk conductivity of silver as opposed to 8% bulk conductivity). At higher curing temperatures (>300??C) inkjet inks were able to achieve conductivities of 33% bulk conductivity of silver. However, these temperatures were not suitable for processing on temperature sensitive surfaces such as carbon fibre. Durability tests showed that silver PTF inks were able to withstand standard aerospace environments apart from Skydrol immersion. It was found that DW inks should achieve a minimum conductivity of 30% bulk silver to reduce antenna and transmission line losses. Using a localised electroplating process (known as brush plating) it was shown that a copper layer could be deposited onto silver inkjet inks and thermoplastic PTF inks with a copper layer exhibiting a bulk conductivity of 66% bulk copper and 57% bulk copper respectively. This was an improvement on previous electroless plating techniques which reported bulk copper conductivities of 50% whilst also enabling DW inks to be plated without the need for a chemical bath. One of the limitations of many DW ink materials is they require curing or sintering before they become functional. Conventional heat treatment is performed using an oven which is not suitable when processing DW materials onto large structural component. Previous literature has investigated laser curing as means of overcoming this problem. However, lasers are monochromatic and can therefore be inefficient when curing materials that have absorption bands that differ from the laser wavelength. To investigate this, a laser diode system was compared to a broadband spot curing system. In the curing trials it was found that silver inks could be cured with much lower energy density (by a factor of 10) using the broadband white light source. Spectroscopy also revealed that broadband curing could be more advantageous when curing DW dielectric ink materials as these inks absorb at multiple wavelengths but have low heat conductivity. Themodynamical modelling of the curing process with the broadband heat source was also performed. Using this model it was shown that the parameters required to cure the ink with the broadband heat source only caused heat penetration by a few hundred micro-metres into the top surface of the substrate at very short exposure times (~1s). This suggested that this curing method could be used to process the DW inks on temperature sensitive materials without causing any significant damage. Using a combination of the developments made in this thesis the RF properties of the DW inks were measured after broadband curing and copper plating. It was found that the copper plated DW ink tracks gave an equivalent transmission line loss to a copper etched line. To test this further a number of GPS patch antennas were fabricated out of the DW ink materials. Again the copper plated antenna gave similar properties to the copper etched antenna. To demonstrate the printing capabilities of the micro-nozzle system a mock wireless telecommunications antenna was fabricated on to a GRP UAV wing. In this demonstrator a dielectric and conductive antenna pattern was fabricated on to the leading edge of the wing component using a combination of convection curing and laser curing (using an 808nm diode laser).
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Haverkos, Stephen M. "FRICTIONAL PROPERTIES OF NOVEL BRACKET SYSTEMS: AN IN-VITRO STUDY." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/5770.
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Orthodontic brackets undergo resistance during sliding that includes classical friction, binding, and notching. Current bracket systems are hampered by these challenging forces. As a result, the clinician usually needs to apply additional forces to overcome the resistance which increases the risk of root resorption and discomfort for the patient. This study evaluated frictional properties of a novel bracket that had polytetrafluoroethylene (Teflon™) coated rollers in its design. Five types of brackets (n = 10, each), including a passive self-ligating bracket, a traditional ligated bracket, a three-dimensionally printed direct metal laser sintering (DMLS) bracket with and without Teflon™ rollers, and computer numeric controlled (CNC) machine milled bracket with Teflon™ rollers were tested. The peak resistance values were assessed at 0°, 4°, and 8° of tip on a 0.019 x 0.025” arch wire. At 8° of tip, the DMLS and the CNC milled bracket systems, both with Teflon™ rollers, exhibited less friction as compared to the other brackets tested (p
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Hussein, Ahmed Yussuf. "The development of lightweight cellular structures for metal additive manufacturing." Thesis, University of Exeter, 2013. http://hdl.handle.net/10871/15023.
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Metal Additive Manufacturing (AM) technologies in particular powder bed fusion processes such as Selective Laser Melting (SLM) and Direct Metal Laser Sintering (DMLS) are capable of producing a fully-dense metal components directly from computer-aided design (CAD) model without the need of tooling. This unique capability offered by metal AM has allowed the manufacture of inter-connected lattice structures from metallic materials for different applications including, medical implants and aerospace lightweight components. Despite the many promising design freedoms, metal AM still faces some major technical and design barriers in building complex structures with overhang geometries. Any overhang geometry which exceeds the minimum allowable build angle must be supported. The function of support structure is to prevent the newly melted layer from curling due to thermal stresses by anchoring it in place. External support structures are usually removed from the part after the build; however, internal support structures are difficult or impossible to remove. These limitations are in contrast to what is perceived by designers as metal AM being able to generate all conceivable geometries. Because support structures consume expensive raw materials, use a considerable amount of laser consolidation energy, there is considerable interest in design optimisation of support structure to minimize the build time, energy, and material consumption. Similarly there is growing demand of developing more advanced and lightweight cellular structures which are self-supporting and manufacturable in wider range of cell sizes and volume fractions using metal AM. The main focuses of this research is to tackle the process limitation in metal AM and promote design freedom through advanced self-supporting and low-density Triply Periodic Minimal Surface (TPMS) cellular structures. Low density uniform, and graded, cellular structures have been developed for metal AM processes. This work presents comprehensive experimental test conducted in SLM and DMLS processes using different TPMS cell topologies and materials. This research has contributed to new knowledge in understanding the manufacturability and mechanical behaviour of TPMS cellular structures with varying cell sizes, orientations and volume fractions. The new support structure method will address the saving of material (via low volume cellular structures and easy removal of powder) and saving of energy (via reduced build-time).
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Ranjan, Rajit. "Design for Manufacturing and Topology Optimization in Additive Manufacturing." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439307951.
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Shukitis, Amber Nicole. "A Recreation and Ballistic Evaluation of Otto Schneeloch's Firearm Curiosity - The .307 Triangular." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5125.
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Otto Scheeloch's U.S. Patent No. 134,442 of 1872 describes a unique firearm that uses triangular bullets. The current research effort evaluates the ballistic performance of Otto's disclosure for the very first time. To achieve this goal it was necessary to seek out surviving artifacts and scour the historical record in search of all the parameters needed to meticulously recreate the curious triangular cartridges and the corresponding gun barrel, with its matching twisted triangular bore. Every aspect of the resulting reproduction ammunition was made to be as authentic as possible, including the use of vintage civil war era bullet lead, bullet grease of period recipe, and the correct type of black powder propellant. 3D CAD (SolidWorksTM) was employed in designing the components, while advanced rapid prototyping (FDM & DMLS) techniques and investment casting were used in the physical construction of the ammunition and barrel. The ballistics testing was performed from a shooting rest over a range of 10-feet. Data was obtained for five rounds using a chronograph, paper targets and ballistic gel. The triangular bullets proved to be surprisingly accurate, consistent, and stable in flight. Data was recorded for sectional density, ballistic coefficient, muzzle velocity and energy, group size and penetration.
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Ghirardi, Lorenzo. "Comportamento a fatica di provini in acciaio inossidabile realizzati tramite DMLS con diverse direzioni di accrescimento." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10665/.
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Si tratta di una tesi svolta su diverse tipologie di provini ottenuti per Direct Metal Laser Sintering. Questi campioni sono stati provati a fatica, precisamente a flessione rotante. Per determinarne il limite di fatica è stato utilizzato il metodo Dixon. Una volta stimato questo valore sono stati svolti degli attacchi chimici per verificare la presenza di cricche e porosità. Infine, per controllare le caratteristiche descritte inizialmente dalla letteratura del materiale, sono stati sottoposti ad una prova di durezza Rockwell.
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Vandi, 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.
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Nel presente lavoro di tesi verrà studiato ed analizzato, tramite prove effettuate in laboratorio, il comportamento a fatica di 3 set di provini metallici in Maraging steel, realizzati mediante le più moderne tecnologie di Additive Manufacturing.
Tale recente tecnologia, pioniera nell'ambito della produzione manifatturiera di prototipi e pezzi, ha iniziato sin dagli inizi del suo sviluppo a mostrare le sue numerose potenzialità, e solo negli ultimi anni ha dimostrato di poter essere applicata con successo anche a componenti meccanici e parti funzionali. Ciononostante, data la modernità della tecnologia, sono richieste ulteriori ricerche ed analisi per determinare il comportamento meccanico di pezzi prodotti con tali tecnologie, in quanto la loro resistenza, statica e soprattutto a fatica, è influenzata dalla peculiarità del processo tecnologico stesso, che tende a generare forte anisotropia nelle leghe metalliche prodotte.
Nella prima parte verranno discussi i fondamenti generali della meccanica per i materiali metallici, in particolare il comportamento dei materiali sottoposti a storie di carico variabile; nella seconda parte verrà presentato uno stato dell'arte dei vari processi di Additive Manufacturing; nella terza parte, verrà studiato il comportamento a fatica, ad alto numero di cicli, dei suddetti provini sottoposti da un macchinario a flessione rotante a vari livelli di carico; nella quarta parte, tramite uso di tecniche statistiche, verrà presentata un'elaborazione dei risultati ottenuti in laboratorio, in particolare per ricavare la curva S-N e il limite di fatica del materiale; infine verrà presentata l'osservazione al microscopio delle superfici di frattura dei provini, per indagare la propagazione della rottura e così risalire alle possibili cause iniziatrici della rottura stessa.
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Asar, Munevver Elif. "Investigating Turbine Vane Trailing Edge Pin Fin Cooling in Subsonic and Transonic Cascades." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu155551385206548.
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Onyeako, Isidore. "Resolution-aware Slicing of CAD Data for 3D Printing." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34303.
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3D printing applications have achieved increased success as an additive manufacturing (AM) process. Micro-structure of mechanical/biological materials present design challenges owing to the resolution of 3D printers and material properties/composition. Biological materials are complex in structure and composition. Efforts have been made by 3D printer manufacturers to provide materials with varying physical, mechanical and chemical properties, to handle simple to complex applications. As 3D printing is finding more medical applications, we expect future uses in areas such as hip replacement - where smoothness of the femoral head is important to reduce friction that can cause a lot of pain to a patient. The issue of print resolution plays a vital role due to staircase effect. In some practical applications where 3D printing is intended to produce replacement parts with joints with movable parts, low resolution printing results in fused joints when the joint clearance is intended to be very small. Various 3D printers are capable of print resolutions of up to 600dpi (dots per inch) as quoted in their datasheets. Although the above quoted level of detail can satisfy the micro-structure needs of a large set of biological/mechanical models under investigation, it is important to include the ability of a 3D slicing application to check that the printer can properly produce the feature with the smallest detail in a model. A way to perform this check would be the physical measurement of printed parts and comparison to expected results. Our work includes a method for using ray casting to detect features in the 3D CAD models whose sizes are below the minimum allowed by the printer resolution. The resolution validation method is tested using a few simple and complex 3D models. Our proposed method serves two purposes: (a) to assist CAD model designers in developing models whose printability is assured. This is achieved by warning or preventing the designer when they are about to perform shape operations that will lead to regions/features with sizes lower than that of the printer resolution; (b) to validate slicing outputs before generation of G-Codes to identify regions/features with sizes lower than the printer resolution.
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Roque, Lidiane Kümpel [UNESP]. "Influência dos tratamentos térmicos na microestrutura e nos micromecanismos de fratura da liga ti-6al-4v produzida por sinterização direta de metal por laser (DMLS)." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/136111.
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000859657.pdf: 11263749 bytes, checksum: 51e907f4fbdf0d8ce56785c1c9af062c (MD5)A liga Ti-6A-4V é um biomaterial que tem se mostrado muito adequado na fabricação de implantes para reparar lesões craniofaciais. Entre outros requisitos, é importante que o implante resista a solicitação mecânica para garantir uma resposta clínica satisfatória de modo a proporcionar conforto e segurança ao paciente. O propósito específico do presente trabalho de pesquisa é determinar a influência de diferentes ciclos térmicos na microestrutura da amostra da Ti-6Al-4V produzida pelo processo de sinterização direta de metal por laser (DMLS) e no micromecanismo de fratura resultante de tensionamento uniaxial em tração. Para isso foram fabricados corpos-de-prova de tração, utilizando a técnica DMLS, e os mesmos foram submetidos a diferentes ciclos térmicos de 650 °C/1h, 650 °C/3h, 800 °C/4h e 850 °C/2h. Posteriormente, os corpos-de-prova foram submetidos a ensaios de tração. A caracterização microestrutural foi realizada com auxílio de microscopia óptica (MO) e eletrônica de varredura (MEV). As superfícies de fratura resultantes para as diferentes condições de ciclos térmicos foram analisadas por microscopia eletrônica de varredura. A microestrutura final da amostra como produzida resultante do processo de manufatura aditiva por DMLS revelou uma microestrutura martensita hexagonal α'. Para a amostra A6501H, a microestrutura martensítica resultante do processo DMLS não se decompôs. Na amostra A6503H a microestrutura martensítica começa a se decompor, pois são observados precipitados da fase β. Já nas amostras A8004H e A8502H observa-se uma estrutura (α +β), com cristais de fase α e fase β precipitada nos contornos. De acordo com a análise fractográfica todas as condições estudadas apresentaram fratura dúctil caracterizada pela formação e coalescência de microcavidades com forma e tamanhos variados
The Ti-6A-4V alloy is a biomaterial that has proved very suitable for the manufacture of prostheses to repair craniofacial injuries. Among other requirements, it is important that the prosthesis resist mechanical stress to ensure a satisfactory clinical response in order to provide comfort and safety to patients. The specific purpose of this research is to determine the influence of thermal cycles - as prototyped, 650 °C (1h); 650 °C (3h), 800 °C (2h) and 850 °C (4h) - on the microstructure and fracture micromechanisms resulting from uniaxial tension in traction. Therefore it was manufactured by DMLS technique bodies - of - proof traction which were subsequently subjected to different thermal cycles. Then, the bodies -specimens were subjected to tensile test. Microstructural characterization was carried out using optical and scanning electron microscopy (SEM). The resulting fracture surfaces of the five conditions for thermal cycling were analyzed by SEM. The final sample microstructure produced as a result of the additive manufacturing process DMLS revealed a hexagonal martensitic microstructure α '. For A6501H sample, the resulting martensitic microstructure DMLS process is not decomposed. In A6503H martensitic microstructure sample begins to decompose, as are observed precipitates of β phase. Already in the samples A8004H and A8502H observe a structure (α + β) with α and β phase crystal phase precipitated in the contours. According to fractographic analysis of all studied showed ductile fracture conditions characterized by the formation and coalescence wells with varying shape and sizes
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Roque, Lidiane Kümpel. "Influência dos tratamentos térmicos na microestrutura e nos micromecanismos de fratura da liga ti-6al-4v produzida por sinterização direta de metal por laser (DMLS) /." Ilha Solteira, 2015. http://hdl.handle.net/11449/136111.
Full textAbstract:
Orientador: Ruís Camargo TokimatsuCo-orientador: Maria Aparecida Larosa
Banca: Vicente Afonso Ventrella
Banca: Cecília Amelia de Carvalho Zavaglia
Resumo: A liga Ti-6A-4V é um biomaterial que tem se mostrado muito adequado na fabricação de implantes para reparar lesões craniofaciais. Entre outros requisitos, é importante que o implante resista a solicitação mecânica para garantir uma resposta clínica satisfatória de modo a proporcionar conforto e segurança ao paciente. O propósito específico do presente trabalho de pesquisa é determinar a influência de diferentes ciclos térmicos na microestrutura da amostra da Ti-6Al-4V produzida pelo processo de sinterização direta de metal por laser (DMLS) e no micromecanismo de fratura resultante de tensionamento uniaxial em tração. Para isso foram fabricados corpos-de-prova de tração, utilizando a técnica DMLS, e os mesmos foram submetidos a diferentes ciclos térmicos de 650 °C/1h, 650 °C/3h, 800 °C/4h e 850 °C/2h. Posteriormente, os corpos-de-prova foram submetidos a ensaios de tração. A caracterização microestrutural foi realizada com auxílio de microscopia óptica (MO) e eletrônica de varredura (MEV). As superfícies de fratura resultantes para as diferentes condições de ciclos térmicos foram analisadas por microscopia eletrônica de varredura. A microestrutura final da amostra como produzida resultante do processo de manufatura aditiva por DMLS revelou uma microestrutura martensita hexagonal α'. Para a amostra A6501H, a microestrutura martensítica resultante do processo DMLS não se decompôs. Na amostra A6503H a microestrutura martensítica começa a se decompor, pois são observados precipitados da fase β. Já nas amostras A8004H e A8502H observa-se uma estrutura (α +β), com cristais de fase α e fase β precipitada nos contornos. De acordo com a análise fractográfica todas as condições estudadas apresentaram fratura dúctil caracterizada pela formação e coalescência de microcavidades com forma e tamanhos variados
Abstract: The Ti-6A-4V alloy is a biomaterial that has proved very suitable for the manufacture of prostheses to repair craniofacial injuries. Among other requirements, it is important that the prosthesis resist mechanical stress to ensure a satisfactory clinical response in order to provide comfort and safety to patients. The specific purpose of this research is to determine the influence of thermal cycles - as prototyped, 650 °C (1h); 650 °C (3h), 800 °C (2h) and 850 °C (4h) - on the microstructure and fracture micromechanisms resulting from uniaxial tension in traction. Therefore it was manufactured by DMLS technique bodies - of - proof traction which were subsequently subjected to different thermal cycles. Then, the bodies -specimens were subjected to tensile test. Microstructural characterization was carried out using optical and scanning electron microscopy (SEM). The resulting fracture surfaces of the five conditions for thermal cycling were analyzed by SEM. The final sample microstructure produced as a result of the additive manufacturing process DMLS revealed a hexagonal martensitic microstructure α '. For A6501H sample, the resulting martensitic microstructure DMLS process is not decomposed. In A6503H martensitic microstructure sample begins to decompose, as are observed precipitates of β phase. Already in the samples A8004H and A8502H observe a structure (α + β) with α and β phase crystal phase precipitated in the contours. According to fractographic analysis of all studied showed ductile fracture conditions characterized by the formation and coalescence wells with varying shape and sizes
Mestre
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Bastos, Jaqueline Silva. "Reparo ósseo em Scaffolds de Ti6Al4V sinterizados pela tecnologia de Sinterização Direta de Metais a Laser (DMLS) submetidos a tratamento de superfície associado à aplicação de ultrassom de baixa intensidade (LIPUS) /." Guaratinguetá, 2016. http://hdl.handle.net/11449/138130.
Full textAbstract:
Orientadora: Ana Paula Rosifini Alves ClaroBanca: André Luiz Jardini Munhoz
Banca: Ricardo Tadeu Lopes
Banca: Orivaldo Lopes da Silva
Banca: Ana Lia Anbinder
Resumo: O objetivo desse estudo in vivo foi verificar a resposta óssea de scaffolds porosos revestidos processados pela técnica de Sinterização Direta de Metais a laser (DMLS) associado à terapia de ultrassom de baixa intensidade. Os scaffolds foram processados empregando a técnica DMLS e tratados termicamente a 1000°C por 24 horas. Três tipos de tratamento de superfície foram avaliados: Alcalino, biomimético e imobilização de alendronato de sódio. Para o tratamento alcalino, as amostras foram imersas na solução de NaOH (5M) a 60ºC por 24 horas. O tratamento biomimético consistiu na imersão dos scaffolds em solução SBF (SimulatedBodyFluid) enquanto a imobilização do alendronato foi realizada a partir da imersão dos scaffolds em uma solução formada por SBF e medicamento durante 5 dias. As superfícies dos scaffolds foram avaliadas para cada etapa empregando microscopia eletrônica de varredura (MEV) e análise por difração de raios-X. Os scaffolds foram implantados na tíbia direita de 85 ratos machos da raça wistar com idade média de 12 semanas. A microtomografia computadorizada (µCT) e análise histológica foram realizadas para avaliar o reparo ósseo no defeito. As micrografias das superfícies obtidas mostraram mudanças no aspecto da superfície e composição química de acordo com o tratamento. O tratamento biomimético promoveu o crescimento da apatita sobre a superfície enquanto a imobilização com alendronato suprimiu sua formação. As imagens obtidas na microtomografia mostraram elevado valor de densidade óssea para o último grupo. No entanto, análises histológicas mostraram a formação de cápsula fibrosa em torno dos scaffolds a qual foi minimizada usando ultrassom pulsado de baixa intensidade. No entanto, mais estudos precisam ser realizados para avaliar a influência da geometria dos scaffolds na incorporação de medicamentos
Abstract: The objective of this in vivo study was to verify the bone response of coated Ti6Al4V porous scaffolds processed by Direct Metal Laser Sintering (DMLS) technique associated to low intensity pulsed ultrasound therapy. Scaffolds were processed by using Direct Metal Laser Sintering technique (DMLS) and heat treated at 1000 °C for 24 hours. Three types of surface treatments were evaluated: alkaline, biomimetic and sodium alendronate immobilization. For alkaline treatment, samples were immersed in a NaOH (5M) solution at 60ºC for 24 hours. Biomimetic treatment consisted in the immersion of the scaffolds into Simulated Body Fluid solution while for sodium alendronato immobilization the scaffolds were immersed in the solution formed by SBF plus drug during 5 days. The scaffolds surfaces were evaluated after each step employing SEM (Scanning Electron Microscopy)and X-rays diffraction analysis(XRD). Scaffolds were implanted into right tibia of 85 male Wistar rats with average age of 12 weeks. X-rays micro-computed tomography (µCT) and histological analysis were carried out to evaluate the bone repair on the defect. Micrographs analysis showed that the aspect of the surfaces and chemical composition changed according treatment. Biomimetic treatment promoted the growth of the apatite on the surface; in contrast the immobilization of alendronate suppressed apatite formation. Micro CT images showed higher value of bone density for the last group. However, histological analysis showed the formation of encapsulation fibrous around the scaffolds. This formation was minimized by using low intensity pulsed ultrasound technique, however, more studies can be carried out to evaluate the influence of scaffolds geometry in the drug incorporation
Doutor
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Tang, Y., Han Tong Loh, J. Y. H. Fuh, Yeow Sheong Wong, L. Lu, Y. Ning, and X. Wang. "Accuracy Analysis and Improvement for Direct Laser Sintering." 2003. http://hdl.handle.net/1721.1/3898.
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The accuracy issue of a rapid prototyping-direct laser sintering system is studied in this paper. The sources of errors are analyzed for their contribution to the final accuracy of built parts. The error sources are related to the hardware and software of the machine, the materials and the process. Special measures were exploited to improve the accuracy of the direct laser sintering system and process. For the errors caused by hardware like laser scanner, compensation by software was developed to correct the errors resulting from galvano-mirrors and F-θ lens. A compensation function mode was added to the slicing software to compensate the errors caused by material shrinkage and laser beam offset. Based on the analysis and improvement, a desired accuracy of 0.2mm has been achieved for the direct laser sintering system, which was verified by experiments.Singapore-MIT Alliance (SMA)
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Lin, Guo-Hui, and 林國輝. "Precision Laser Direct-Write Sintering Technology for Silver Nanoparticles." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/qt375h.
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碩士國立虎尾科技大學
光電與材料科技研究所
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The film display technology is growing mature, so the size of films is growing larger as well. It is very wasteful and resources unwise to generate circuit wire only in part of the area by plating the whole panel with mask. Therefore, we improve that disadvantage by adopting laser direct-write technique on the glass substrate to implant silver wire. The laser direct-write technique uses the blue-ray optical pickup as the resource of light, and it is a focusing lens with 405nm wavelength and 0.85 N.A. (numerical aperture). The characteristics above make it able to shrink the resource of light to 19% of the red-ray optical pickup. The sample specimen used in the experiment needed to coat the nano-silver solution on the glass substrate first, and then took advantage of the PDIC (photo diode integrated circuit) inside of the optical pickup to receive the FES (focus error signal) reflected by the glass substrate. It is used to distinguish whether the laser spot is on the positive focus and it can further achieve the atomization of the lock focus with VCM (voice coil motor) and with Labview program which controls the up and down displacement. It can shorten the manufacture process and decrease errors by human tuning. The patterned substrate is contained on the nano-platform and it controls the light energy of the optical pickup by the platform mobile and programs to get the effect of direct-write silver solution. The line width can up to 400 nm according to our test result.
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Olwagen, Annalene. "An investigation into the deformation of direct metal laser sintered parts / Annalene Olwagen." Thesis, 2015. http://hdl.handle.net/10394/15489.
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Direct Metal Laser Sintering (DMLS) is a rapid prototyping technique that allows for direct and rapid manufacturing of complex components. DMLS is however an intricate process and the quality of the final product is influenced by multiple manufacturing parameters (or DMLS settings) and powder characteristics. The effect which each of these manufacturing parameters and powder characteristics has on the final parts is not well understood and the success of process manufacturing mainly relies on empirical knowledge. Consequently high dimensional deformation and relatively poor mechanical properties are still experienced in many DMLS products, in particular in copper-based laser sintered parts.
A need therefore exists to systematically examine the effect of process parameters on the quality of final parts in order to determine the most appropriate manufacturing parameters for specific applications of copper-based laser sintered parts.
This document summarises the effect of different process parameters on the quality of Direct Metal 20 laser sintered parts produced with a EOSINT M250 Xtended laser sintering machine from powder consisting of Ni5Cu, Cu15Sn – Cu5Sn and Cu8P – Cu2P material grains.
The quality of the sintered parts is defined in terms of the microstructures, porosities and dimensional deformations obtained.
The effects of three different geometric sintering strategies currently in standard use namely Solid Skin, Skin Stripes and Skin Chess were examined, and the more appropriate process parameters and scanning technique for the available set-up is presented.MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2015
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Wright, Christopher S., K. W. Dalgarno, and M. M. Dewidar. "Processing conditions and mechanical properties of high speed steel parts fabricated using direct selective laser sintering." 2003. http://hdl.handle.net/10454/4129.
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NoThis paper reports the results of an investigation into the selective laser sintering of a prealloyed high-speed steel powder. The structured development of processing conditions for single lines, single layers and multiple layers of material is reported, as are the flexural modulus and strength of the single- and multiple layer components. Infiltration with bronze was used to improve the mechanical properties of the components and it is concluded that selective laser sintering of high-speed steel allied to bronze infiltration can produce material with the mechanical properties to allow for use in load-bearing applications, but that further work is required to improve the density, mechanical properties and build rate if selective laser sintering is to develop as a general manufacturing process for hard metals.
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Alayavalli, Kaushik Comandoor. "Design, fabrication and testing of graphite bipolar plates for direct methanol fuel cells by indirect laser sintering." Thesis, 2011. http://hdl.handle.net/2152/ETD-UT-2011-08-3894.
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Direct Methanol Fuel Cells (DMFCs) are electrochemical energy conversion devices that convert chemical energy into electrical energy. The bipolar plate component of the DMFC is required to be fluid impermeable to prevent fuel leakage and electrically conductive to collect the electrons produced within the cell. Graphite possesses the properties of high electrical conductivity, low weight and resistance to corrosion that make it an attractive material for bipolar plates. However, the poor mechanical properties of graphite lead to prohibitive machining costs and increased production times. The objective of this research is to develop an indirect laser sintering (LS) process, involving the laser sintering of graphite powders mixed with a phenolic resin binder which offers the advantage of complex part production and testing of prototype bipolar plates in short times. Due to the nature of the indirect LS process, the as-produced (green part) plates are porous and possess low electrical conductivities (< 0.1 S.cm-1).
This research describes a viable method to rapidly fabricate and test multiple graphite bipolar plate designs using indirect LS. This process involved identifying and selecting suitable graphite powder and binder systems based on their thermal and electrical properties and developing a post process heat treatment method for achieving electrical conductivity of 250 S/cm for LS graphite parts which exceeds the DOE target of 100 S/cm for bipolar plate materials. The post processing also covered a method of infiltration using cyanoacrylate which was capable of rendering porous brown parts fluid impermeable and suitable for use in DMFCs. The cyanoacrylate infiltrated LS graphite parts were characterized for flexural strength and electrical and thermal conductivities and bipolar plates were made and evaluated in a DMFC test stand.
Various flow field designs including plates with varying channel and rib widths and triangular, elliptical and rectangular flow field cross sections were fabricated using indirect LS and their respective polarization curves were compared to commercially machined graphite plates. The fuel cell tests show the improvement in mass transport performance could be due to improved methanol distribution and water removal characteristics of triangular and elliptical cross sectional channels over rectangular channels of equivalent dimensions.text
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Sousa, André Diogo Roberto de. "Orientation and location dependency of the mechanical properties of an AlSi10Mg part produced using direct metal laser sintering (DMLS) - a microsample approach." Dissertação, 2017. https://repositorio-aberto.up.pt/handle/10216/108284.
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Sousa, André Diogo Roberto de. "Orientation and location dependency of the mechanical properties of an AlSi10Mg part produced using direct metal laser sintering (DMLS) - a microsample approach." Master's thesis, 2017. https://repositorio-aberto.up.pt/handle/10216/108284.
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(5931092), Ehsan Maleki Pour. "Innovative Tessellation Algorithm for Generating More Uniform Temperature Distribution in the Powder-bed Fusion Process." Thesis, 2019.
Find full textAbstract:
Powder Bed Fusion Additive Manufacturing enables the fabrication of metal parts with complex geometry and elaborates internal features, the simplication of the assembly process, and the reduction of development time. However, the lack of consis-tent quality hinders its tremendous potential for widespread application in industry. This limits its ability as a viable manufacturing process particularly in the aerospace and medical industries where high quality and repeatability are critical. A variety of defects, which may be initiated during the powder-bed fusion additive manufacturing process, compromise the repeatability, precision, and resulting mechanical properties of the final part. The literature review shows that a non-uniform temperature distribution throughout fabricated layers is a signicant source of the majority of thermal defects. Therefore, the work introduces an online thermography methodology to study temperature distribution, thermal evolution, and thermal specications of the fabricated layers in powder-bed fusion process or any other thermal inherent AM process. This methodology utilizes infrared technique and segmentation image processing to extract the required data about temperature distribution and HAZs of the layer under fabrication. We conducted some primary experiments in the FDM process to leverage the thermography technique and achieve a certain insight to be able to propose a technique to generate a more uniform temperature distribution. These experiments lead to proposing an innovative chessboard scanning strategy called tessellation algorithm, which can generate more uniform temperature distribution and diminish the layer warpage consequently especially throughout the layers with either geometry that is more complex or poses relatively longer dimensions. In the next step, this work develops a new technique in ABAQUS to verify the proposed scanning strategy. This technique simulates temperature distribution throughout a layer printed by chessboard printing patterns in powder-bed fusion process in a fraction of the time taken by current methods in the literature. This technique compares the temperature distribution throughout a designed layer printed by three presented chessboard-scanning patterns, namely, rastering pattern, helical pattern, and tessellation pattern. The results conrm that the tessellation pattern generates more uniform temperature distribution compared with the other two patterns. Further research is in progress to leverage the thermography methodology to verify the simulation technique. It is also pursuing a hybrid closed-loop online monitoring (OM) and control methodology, which bases on the introduced tessellation algorithm and online thermography in this work and Articial Neural Networking (ANN) to generate the most possible uniform temperature distribution within a safe temperature range layer-by-layer.
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Maleki, Pour Ehsan. "Innovative Tessellation Algorithm for Generating More Uniform Temperature Distribution in the Powder-bed Fusion Process." Thesis, 2018. http://hdl.handle.net/1805/17386.
Full textAbstract:
Purdue School of Engineering and Technology, IndianapolisPowder Bed Fusion Additive Manufacturing enables the fabrication of metal parts with complex geometry and elaborates internal features, the simplification of the assembly process, and the reduction of development time. However, the lack of consistent quality hinders its tremendous potential for widespread application in industry. This limits its ability as a viable manufacturing process particularly in the aerospace and medical industries where high quality and repeatability are critical. A variety of defects, which may be initiated during the powder-bed fusion additive manufacturing process, compromise the repeatability, precision, and resulting mechanical properties of the final part. The literature review shows that a non-uniform temperature distribution throughout fabricated layers is a significant source of the majority of thermal defects. Therefore, the work introduces an online thermography methodology to study temperature distribution, thermal evolution, and thermal specifications of the fabricated layers in powder-bed fusion process or any other thermal inherent AM process. This methodology utilizes infrared technique and segmentation image processing to extract the required data about temperature distribution and HAZs of the layer under fabrication. We conducted some primary experiments in the FDM process to leverage the thermography technique and achieve a certain insight to be able to propose a technique to generate a more uniform temperature distribution. These experiments lead to proposing an innovative chessboard scanning strategy called tessellation algorithm, which can generate more uniform temperature distribution and diminish the layer warpage consequently especially throughout the layers with either geometry that is more complex or poses relatively longer dimensions. In the next step, this work develops a new technique in ABAQUS to verify the proposed scanning strategy. This technique simulates temperature distribution throughout a layer printed by chessboard printing patterns in powder-bed fusion process in a fraction of the time taken by current methods in the literature. This technique compares the temperature distribution throughout a designed layer printed by three presented chessboard-scanning patterns, namely, rastering pattern, helical pattern, and tessellation pattern. The results confirm that the tessellation pattern generates more uniform temperature distribution compared with the other two patterns. Further research is in progress to leverage the thermography methodology to verify the simulation technique. It is also pursuing a hybrid closed-loop online monitoring and control methodology, which bases on the introduced tessellation algorithm and online thermography in this work and Artificial Neural Networking (ANN) to generate the most possible uniform temperature distribution within a safe temperature range layer-by-layer.