Дисертації з теми "Powder printing"
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Lee, Sang-Joon John. "Powder layer generation for three dimensional printing." Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/12452.
Повний текст джерелаFan, Tailin. "Droplet-powder impact interaction in three dimensional printing." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10948.
Повний текст джерелаBredt, James Frederic. "Binder stability and powder/binder interaction in three dimensional printing." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/10999.
Повний текст джерелаSaxton, Patrick C. (Patrick Charles) 1975. "Reducing powder bed layer defects in slurry-based three dimensional printing." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/9423.
Повний текст джерелаIncludes bibliographical references (leaf 141).
Slurry-based Three Dimensional Printing is being used to create ceramic parts directly from CAD files. Discrete slurry layers are deposited, into which a binder material is selectively ink-jet printed. This process is repeated until the last layer of the powder bed is deposited. Afterwards, the powder bed is re-dispersed in water, leaving behind the printed green part. The green part is then sintered to full density. This thesis focuses on methods of depositing the slurry layers. Currently, slurry layers are deposited by nozzle rastering. In this approach, a nozzle mounted to an x-y linear positioning system deposits adjacent discrete lines of slurry on a powder bed. Powder beds produced by nozzle rastering contain defects that occur between line and layer interfaces. The top surface has an inherent roughness due to the peaks and valleys between discrete lines. Line merging is a new method of slurry layer deposition that has been developed in an effort to eliminate inter-line defects, improve layer surface finish, and increase throughput This new technique has been used to rapidly produced slurry layers containing fewer internal defects and smooth surface finishes. Line merging occurs when adjacent lines of slurry are deposited in rapid succession such that they merge together prior to slip casting. Line merging differs from nozzle rastering in two ways: lines are deposited in only one direction (during the return pass the nozzle is put into a catch position), and the cycle time between depositing lines is reduced from approximately I second to as little as 0.1 second. A model was developed in an effort to identify the conditions required to achieve successful line merging, while avoiding layer defects such as bubbling and irregular surface finish caused by slurry migration. This model emphasized three relationships: the ratio of cycle time for line deposition to slip casting time for a slurry layer, the ratio of line width to line spacing, and the inverse of the width of the wet slurry zone where lines have merged prior to slip casting. A 3-D plot was constructed relating an objective function comprised of the three relationships to the control parameters (flow rate divided by nozzle velocity and cycle time). A plot for each alumina slurry solids loading was used to guide experiments. These experiments supported the model, though some relationships were proved more accurate than others. The model was ultimately used to target the ideal line merging conditions that were used to produced a 60 layer alumina powder bed out of 50 micron thick layers of 18 vol% alumina slurry. This powder bed exhibited excellent surface finish, with a maximum variation of 11 microns peak to valley. SEM analysis of cross-sections revealed that internal defects between deposited lines, previously seen with nozzle rastering, had been eliminated. Micro-bubbles along the interface between layers persisted, however. Follow-up SEM analysis of a 5 layer powder bed built with 22 vol% alumina slurry revealed no inter-line or inter-layer defects.
by Patrick C. Saxton.
S.M.
Esterman, Marcos. "Characterization of the powder/binder interaction in the three dimensional printing process." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/13671.
Повний текст джерелаTitle as it appears in the Sept. 1990 M.I.T. Graduate List: Characterization of powder/binder interaction in the three dimensional printing process.
Includes bibliographical references (leaves 131-132).
by Marcos Esterman, Jr.
M.S.
Nur, Hassan Mohammed. "Fabrication of advanced ceramics and selective metallization of non-conductive substrates by inkjet printing." Thesis, Brunel University, 2002. http://bura.brunel.ac.uk/handle/2438/4823.
Повний текст джерелаTouma, Rikard, and Nathalie Pettersson. "3D-printing med träEn möjlighet för framtiden?" Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-92364.
Повний текст джерела3D printers have many uses and they have become common in many industries. Today, thistechnology is seen as a possible route to more sustainable construction. The technology isconsidered promising in construction engineering, among other things because it has beenshown that it can reduce material waste and provide shorter production times. To someextent, the technology is already being used for building construction, but then mainly withconcrete.The aim of this study is to describe current knowledge regarding 3D printing with woodbasedpulp and to investigate the possibility of using a wood-based pulp consisting ofsawdust, water and lignin for 3D printing.In order to reach the goal, a combination of literature search and laboratory experiments wasused. The literature search was used both to investigate previously conducted studiesregarding wood-pulp based materials in 3D printing and as inspiration for the ingredients andproportions used in the laboratory experiments.Only studies on wood-based 3D printing were studied. The test objects produced in thelaboratory experiments were evaluated in strength, dimensional stability and adhesion. Theresults of the laboratory work indicate that the produced material can be extruded, but that ithas low tensile strength. The layers bonded well for all tests, while the compressive strengthresults varied. The highest compressive strength was given by the mixture with the highestproportion of lignin and the longest drying time.The conclusion is that the material might be useful, but that the correct area of use should bedetermined, as the material cannot withstand excessive loads.Keywords:
Pruitt, Beth L. (Beth Lynn). "The design of an automated powder deposition system for a three-dimensional printing machine." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/13049.
Повний текст джерелаRamos, Juan David. "Design of humidifying system for the powder bed of the three-dimensional printing machine." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/12442.
Повний текст джерелаCaradonna, Michael Anthony. "The fabrication of high packing density ceramic powder beds for the three dimensional printing process." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/9316.
Повний текст джерелаIncludes bibliographical references (leaf 123).
Three Dimensional Printing is a solid freeform fabrication process which can be used to create parts directly from CAD models. In the past, the 3DP process has been used to create structural ceramic parts using spray dried powders. Although fully dense parts have been made, it has been necessary to use an iso-static pressing step before sintering. Such a step has many disadvantages such as causing anisotropic shrinkage, warping, and lower part yields. In order to eliminate the iso-static pressing step, an improved process which uses slurries instead of dry powders makes it possible to fabricate green parts with high enough packing density that printed parts can be sintered directly. The main effort on the slurry-based 3DP process focused on fabricating powder beds which had high packing density and good surface finish. Three possible approaches were investigated: repeated tape-casting, spray deposition, and ink-jet printing of slurry. The repeated tape-casting approach was able to produce powder beds with excellent surface finish (4 [mu]m peak-to-peak roughness), high packing density (60-65% of theoretical), and small pore size (typically 0.3 [mu]m or less). Such powder beds can also be fabricated relatively quickly since a layer is produced in a single pass. However, this approach can be difficult to control. The spray deposition approach was determined to be a poor candidate for layer fabrication. Besides having relatively rough surface finish, nozzle performance problems make it impossible to build thick powder beds with good dimensional control. The ink-jet printing approach has produced large powder beds up to 8.5 mm in height. For such powder beds, good surface finish (8 [mu]m local peak-to-peak roughness) and dimensional control was evident. Ink-jet printed powder beds also have good packing density (55-62% of theoretical) and pore size distribution. One problem with powder beds which have been printed is that velocity ripple in the fast-axis shows up as a height ripple on the powder bed surface (typically 4.5% peak-to-peak). This can be eliminated with improved machine design. The ink-jet printing approach appears to be the leading method of fabricating complex ceramic parts with the slurry-based 3DP process.
by Michael Anthony Caradonna.
S.M.
Gregorski, Steven Joseph. "High green density metal parts by vibrational compaction of dry powder in three dimensional printing process." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/8179.
Повний текст джерелаIncludes bibliographical references (p. 395-399).
The material properties and dimensional accuracy of metal tooling produced by the Three Dimensional Printing process can be enhanced by increasing the green density of the 3D printed part. Green density is the ratio of metal powder volume to the external volume of the printed part, and is a measure of how tightly packed the powder particles in the printed part are. The central goal of this thesis was to increase the green density of metal parts from the current level of 58% to levels greater than 75%. Two approaches were taken for increasing green density. The first was to utilize bimodal mixtures of metal powders which could be packed to significantly higher densities than the monomodal powders which had been previously used. Three bimodal powder mixtures, with tap densities near 80%, were studied. The second approach was to develop a new powder layering device which could pack these bimodal powders to the tap density during layer creation. New understandings about the relationship between the stresses applied to the powder layer and the resulting packing density changes were required to design this device. Shear cell and unconfined compression tests were performed to characterize the metal powder stress / strain behavior. Particulate stress / strain models, such as the Mohr-Coulomb failure law and the Jenike yield locus theory, were used to interpret the packing behavior of the metal powders under various stress conditions.
(cont.) A simple frictional model of powder behavior was proposed for the low stress levels permissible in the 3DP process. The application of a small static normal stress, in combination with an oscillatory horizontal shear stress, was found to be the most effective means of reducing particle interlocking and provided the best layer densification results. A new layer densification mechanism was constructed and successfully used to generate printed parts with green densities in excess of 75%. Photographic analysis techniques used to analyze part microstructures indicated significant improvements in packing homogeneity. Packing defects between the printed layers were reduced or eliminated. Compositional analysis indicated no significant segregation of the bimodal components during layer spreading.
by Steven Joseph Gregorski.
Ph.D.
Charnnarong, Jain. "The drying shrinkage in three-dimensional printing and its dependence on the properties of the powder and the binder." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10950.
Повний текст джерелаFitzgerald, Shawn. "A pneumatic conveying powder delivery system for continuously heterogeneous material deposition in solid freeform fabrication." Thesis, Virginia Tech, 1996. http://hdl.handle.net/10919/46072.
Повний текст джерелаGreat improvements are continuously being made in the solid free form fabrication (SFF) industry in terms of processes and materials. Fully functional parts are being created directly with little, if any, finishing. Parts are being directly fabricated with engineering materials such as ceramics and metals. This thesis aims to facilitate a substantial advance in rapid prototyping capabilities, namely that of fabricating parts with continuously heterogeneous material compositions. Because SFF is an additive building process, building parts layer-by-layer or even point-by-point, adjusting material composition throughout the entire part, in all three dimensions, is feasible. The use of fine powders as its build material provides the potential for the Selective Laser Sintering (SLS), ThreeDimensional Printing (3DP), and Freeform Powder Molding (FPM) processes to be altered to create continuously heterogeneous material composition. The current roller distribution system needs to be replaced with a new means of delivering the powder that facilitates selective heterogeneous material compositions. This thesis explores a dense phase pneumatic conveying system that has the potential to deliver the powder in a controlled manner and allow for adjustment of material composition throughout the layer.
Master of Science
Caputo, 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.
Повний текст джерелаGoss, Cullen. "SLM 125 Single Track and Density Cube Characterization for 316L Stainless Steel." DigitalCommons@CalPoly, 2019. https://digitalcommons.calpoly.edu/theses/2050.
Повний текст джерелаHrabal, Michal. "Development of Light Emitting Electroluminescent Device by Means of Material Printing." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-402111.
Повний текст джерелаWestbeld, Julius. "Investigation of support structures of a polymer powder bed fusion process by use of Design of Experiment (DoE)." Thesis, KTH, Lättkonstruktioner, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-243867.
Повний текст джерелаI detta examensarbete undersöks stödstrukturer för en polymer-pulverbaserad process kallad XXXXXXXX. Dessa strukturer är väsentliga för de flesta aditiv tillverkning. Med hjälp av metoden "Design of Experiment" (DoE) undersöks effekten av flera faktorer på fem industriellt viktiga egenskaper för stödstrukturer. DoE beskriver både planeringen och analysen av experiment. Experimenten planeras i en fraktionerad faktoriell 211-5 design med 64 provexemplar vilket resulterar i en upplösning av IV. Dataanalysen genomförs med hjälp av ANOVA-metoden, med vilken signifikansen av effekter och interaktionseffekter kan undersökas.
Clark, Jared A. "The Effects of Build Orientation on Residual Stresses in AlSi10Mg Laser Powder Bed Fusion Parts." Youngstown State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1578819644598848.
Повний текст джерелаMiller, Jacob T. "Sulfuric Acid Corrosion to Simulate Microbial Influenced Corrosion on Stainless Steel 316L." Youngstown State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ysu151621775594905.
Повний текст джерелаFan, Zongyue. "A Lagrangian Meshfree Simulation Framework for Additive Manufacturing of Metals." Case Western Reserve University School of Graduate Studies / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=case1619737226226133.
Повний текст джерелаSeluga, Kristopher J. (Kristopher Joseph) 1978. "Three dimensional printing by vector printing of fine metal powders." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/85726.
Повний текст джерелаBaker, Peter R. (Peter Ross). "Three dimensional printing with fine metal powders." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/46287.
Повний текст джерелаIncludes bibliographical references (leaf 97).
In the area of direct metal part manufacture, the 3DPTM process has several inherent advantages over traditional machining and P/M technologies: hard tooling is not required to manufacture parts, geometries may be created which can not be made by conventional processes, and the composition of parts may be controlled locally on a 100 gm scale. The surface finish of 3DPTM parts will be a key factor in the determination of what parts are candidates for direct manufacture via the 3DPTM process. Powder size is the limiting factor in the determination of the surface finish of 3DPTM parts. On the micro scale, it determines the roughness due to particle arrangement, and on the macro scale it determines the thinnest layers from which parts may by built. The 3DPTM process has been adapted to a fine metal powder (ten micron particle diameter) material system. Powder spreading, ink-jet technology, and the effect of print parameters on printing with fine metal powders have been examined. Powder spreading experiments were conducted to examine the limits of layer thickness and packing density. 420 ss, S-7 tool steel, and 316L ss powderbed beds were generated in fifty micron layers. Packing densities of 55%, 59% and 59% respectively were obtained for the three powders. Line printing experiments were conducted with both continuous jet (CJ) and drop on demand (DOD) printheads to examine the relationship between droplet frequency, droplet spacing and the quality of printed lines. Lines were printed at droplet frequencies ranging from 100 Hz to 40 kHz and with droplet spacings from ten to fifty microns. Low print frequencies and small droplet spacings result in the highest quality lines. A droplet spacing of thirty microns and a droplet frequency of 667 Hz was chosen for the printing of 3-D parts with a Hewlett- Packard DOD printhead. 3-D part geometries were generated using fifty micron layers of ten micron 420 ss powder. These parts demonstrated the improvement in surface finish achieved with fine metal powders and the capability to create parts from fields identified as promising for the direct fabrication of metal parts via the 3DPTM process.
by Peter R. Baker, Jr.
S.M.
GROPPO, RICCARDO. "Sviluppo e Industrializzazione di una macchina LPF e validazione attraverso l'ottimizzazione dei parametri di processo di Ottone CuZn42 e Acciaio Armonico C67." Doctoral thesis, Università degli studi di Modena e Reggio Emilia, 2021. http://hdl.handle.net/11380/1245517.
Повний текст джерелаThe additive manufacturing technologies, from their birth to the first industrial applications, made a big jump in terms of hardware and material development. The continuing research for new markets along with a growing demand have made sure that the costs of such technologies have become more accessible. From the using of polymers to do prototypes to metal powders to do real mechanical parts the concepts are always the same, building the part layer by layer. In terms of money from the eighties to present days the 3D printing process maintain a positive trend with much more increases for the future. In terms of monetary and energy flows during the production of complex parts, the additive manufacturing technologies can have positive increments. Thus the adoption of Additive Manufacturing also simplifies measurement of the manufacturing energy consumption for life cycle inventory assessments. In many traditional supply chains, where reliable estimates of cumulative energy consumption may be unavailable, the adoption of AM allows producers to provide their customers with reliable data on the energy embedded into products or component during the manufacturing stage. It has been shown that selecting the minimum cost configuration in Additive Manufacturing is likely to lead to the secondary effect of minimizing process energy consumption. My PhD thesis will discuss a specific additive manufacturing technology, based on the powder bed fusion process using a LASER as a melting source. The main construction components present in the prototype machine will be analyzed, looking for the main critical issues (filtering and powder recovery system, black powder abatement system, in-chamber gas flow, measurement of load losses in the characteristic sections of the plant, powder collection system, distribution and powder deposition system on the printing plate) and, if these cause a crash or an irregularity in the quality in the printed component, a radical modification or replacement of this component will develop. Once the mechanical stability of the entire machine has been verified, the mechanical properties of the samples obtained with stainless steel X2CrNiMo17-12-2 - AISI316L, CuZn42 brass powder and C67 steel - Tempered steel will be analyzed. The main mechanical properties required for a component built for additive manufacturing are in terms of mechanical strength porosity, density, hardness, ultimate tensile strength, and yield tension. Measurements of the density of the specimen will be carried out by measuring the relative volumetric density by Archimedes method. Subsequently, the quality of surface roughness will be measured through the acquisition of maps by means of an optical microscope and through an image analysis software the average surface roughness will then be measured. The same sample will then be used to measure the average hardness of the material by means of a durometer. To test the ultimate tensile strength and the yield strength, samples with circular section will be produced to which an analog extensometer will be mounted. Data processing software processes the strain -strain curve.
Zubricky, James R. III. "Physical Models of Biochemicallly Important Molecules Using Rapid Prototyping Techniques." Bowling Green State University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1151350496.
Повний текст джерелаNorton, Joseph. "Bronze powders - a study of the surface coating." Thesis, University of Huddersfield, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239691.
Повний текст джерелаCestari, Francesca. "3D printing of bone scaffolds using powders derived from biogenic sources." Doctoral thesis, Università degli studi di Trento, 2023. https://hdl.handle.net/11572/363403.
Повний текст джерелаRamírez, Jiménez Guillermo. "Electric sustainability analysis for concrete 3D printing machine." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-258928.
Повний текст джерелаNumera blir tillverkningstekniken alltmer medveten om effektivitet och hållbarhet. En av dem är den så kallade 3Dutskriften. Medan 3Dutskrift ofta är kopplad till plast, är verkligheten att det finns många andra material som testas, vilket kan ha flera förbättringar över plast.Ett av dessa alternativ är sten eller betong, vilket är mer lämpligt inom arkitektur och konstnärliga fält. På grund av sin natur inbegriper denna nya teknik användningen av nya tekniker jämfört med de vanligare 3Dskrivarna. Detta innebär att det kan vara intressant att veta hur mycket mer energieffektiva dessa tekniker är och hur de kan förbättras i framtida revisioner.Denna avhandling är ett försök att studera och analysera de olika enheter som utgör en av dessa skrivare och med denna information, bygga en modell som exakt beskriver dess beteende.För detta ändamål mäts effekten på många punkter och senare analyseras och anpassas den till en fördefinierad funktion. Efter anpassning har gjorts beräknas felet för att visa hur exakt modellen är jämfört med originaldata.Det visade sig att många av dessa enheter producerar spänningsspikar på grund av dess olinjära beteende. Detta beteende är vanligtvis relaterat till omkoppling och kan undvikas med olika enheter.Slutligen ges några råd om framtida forskning och revideringar, vilket kan vara till hjälp för säkerhet, effektivitet och kvalitet.
Gregory, Scott W. "‘The Wuding Editions’: Printing, Power, and Vernacular Fiction in the Ming Dynasty." BRILL ACADEMIC PUBLISHERS, 2017. http://hdl.handle.net/10150/625956.
Повний текст джерелаDas, Ajay Kumar. "An investigation on the printing of metal and polymer powders using electrophotographic solid freeform fabrication." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0005385.
Повний текст джерелаMa, Da. "Improving the Strength of Binder Jetted Pharmaceutical Tablets Through Tailored Polymeric Binders and Powders." Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/101030.
Повний текст джерелаM.S.
Three-dimensional printing is well-known as 3D printing. 3D printing pills are printed from the 3D printer. As of today, we now stand on the brink of a fourth industrial revolution. By the remarkable technological advancements of the twenty-first century, manufacturing is now becoming digitized. Instead of using a large batch process as traditional, customized printlets with a tailored dose, shape, size, and release characteristics could be produced on- demand. The goal of developing pharmaceutical printing is to reduce the cost of labor, shorten the time of manufacturing, and tailor the pills for patients. And have the potential to cause a paradigm shift in medicine design, manufacture, and use. This paper aims to discuss the current and future potential applications of 3D printing in healthcare and, ultimately, the power of 3D printing in pharmaceuticals.
Ehlert, Ryan. "The design of a volumetric dispensing system for free-flow powders used in three dimensional printing." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/11605.
Повний текст джерелаDoshi, Parag Mahendra. "Fundamental understanding and integration of rapid thermal processing, PECVD, and screen printing for cost-effective, high-efficiency silicon photovoltaic devices." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/14783.
Повний текст джерелаSharan, Kumar Varun. "Study of Binding Copper Powders by Electrochemical Deposition." University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1471346137.
Повний текст джерелаZhao, Kunchen. "3D Printed Frequency Scanning Slotted Waveguide Array with Wide Band Power Divider." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1555589955819802.
Повний текст джерелаJoshi-Kumar, Monica. "Headspace Analysis of Smokeless Powders: Development of Mass Calibration Methods using Microdrop Printing for Chromatographic and Ion Mobility Spectrometric Detection." FIU Digital Commons, 2010. http://digitalcommons.fiu.edu/etd/150.
Повний текст джерелаStephenson, Joshua A. "A Study of RF/Microwave Components Using Fused Deposition Modeling and Micro-Dispensing." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6955.
Повний текст джерелаThienen, Stefan, and Thomas Gellner. "Flexible and easy to engineer servo-hydraulic actuators using 3D printing manufacturing process." Technische Universität Dresden, 2020. https://tud.qucosa.de/id/qucosa%3A71208.
Повний текст джерелаFeng, Ziang. "Wearable Power Sources and Self-powered Sensors Based on the Triboelectric Nanogenerators." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/103020.
Повний текст джерелаPh.D.
Portable electronic devices have become important components in our daily lives, and we are entering the era of the Internet of Things (IoTs), where everyday objects can be interconnected by the internet. While electricity is essential to all of these devices, the traditional power sources are commonly heavy and bulky and need to be recharged or directly connected to the immobile power plants. Researchers have been working to address this mismatch between the device and power systems. The triboelectric nanogenerators (TENG) are good candidates because they can harvest energy in the ambient environment. The users can use them to generate electricity by merely making the rubbing motion. In this work, we report two fabrication methods of the fiber-based triboelectric nanogenerators (FTENG). With the thermal drawing process, we have fabricated sub-kilometer-long FTENG and wove it with the regular cotton yarn into textiles. The wearable power source is human friendly as it does not induce any extra weight load for the user. Besides, we have demonstrated that such long fibers can work as self-powered distributed sensors, such as a Morse code generator. With 3D printing, we have fabricated FTENG-based devices that conform to the working substrates, which can be any shape. We have employed them as biofriendly sensors to translate the chin movement during speaking to language and to monitor the perfusion rate of a pig kidney. The FTENGs have offered excellent comfortability to the users and can play a vital role in reframing the power structure to be compatible with IoTs.
Wienhausen, Arne Hendrik [Verfasser], Doncker Rik W. [Akademischer Betreuer] De, and Andrei [Akademischer Betreuer] Vescan. "High integration of power electronic converters enabled by 3D printing / Arne Hendrik Wienhausen ; Rik W. de Doncker, Andrei Vescan." Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://d-nb.info/1220082368/34.
Повний текст джерелаJiang, Chen. "All-inkjet-printed low-voltage organic thin-film transistors." Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/285012.
Повний текст джерелаMitchell-Williams, Thomas Benjamin. "Tailoring superconductor and SOFC structures for power applications." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/267811.
Повний текст джерелаStephen, Juanita Peche. "3-D Printing, Characterizing and Evaluating the Mechanical Properties of 316L Stainless Steel Materials with Gradient Microstructure." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/102780.
Повний текст джерелаMaster of Science
The mechanical performance of Selective Laser Melting (SLM) fabricated materials is an important topic in research. Strengthening the performance of these materials can be achieved through implementing a gradient within the microstructure, referred to as Materials with Graded Microstructure (MGMs). A complicated microstructure can weaken the microstructure, and this can be resolved by optimizing the microstructure during SLM 3D printing, in which the processing parameters are tailored. In this study, the mechanical properties of these MGMs were characterized and evaluated. The gradient in these materials were created by modifying SLM process parameters (scanning speed, hatch spacing, and laser power and scanning speed) during the build. Optical and scanning electron microscopy (SEM) was used to characterize these the microstructure of these MGMs, and image processing was used to examine the distribution of cells and melt pools characteristics throughout the region where the processing parameters changed. This investigation shows that laser power, scanning speed, and hatch spacing have a direct effect on the size and shape of the cells and melt pools, compared to scanning speed, which shows an effect on melt pools. Dog bone structures are 3-D printed with a graded microstructure that has small cells and melt pools at the edges, compared to the center, by changing the laser power and scanning speed. Tensile and fatigue analysis are performed and compared for samples with constant and graded microstructures, which reveal that the mechanical properties of the MGMs perform similar to the parameter at the edges, but differently in fracture mechanics.
Stratton, John W. i. "A Study of Direct Digital Manufactured RF/Microwave Packaging." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/6031.
Повний текст джерелаKarpavičius, Povilas. "Ofsetinės ir fleksografinės spaudos kokybės palyginimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2007. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2007~D_20070629.145854-26727.
Повний текст джерелаIn master thesis was compared the offset and flexographic printing quality. Printing quality was evaluated using control strips, register crosses, resolving power test elements. Jobs were printed with offset sheet-fed printing press and flexographic narrow web press with central impresion cilinder. Register accuracy and resolving power were investigated using microscope. Dot area of single and binary colors wes measured with densitometer and halftone graduation characteristics were evaluated. On the basis of quantitative results it was determined that offset printing quality in comparison with flexography is higher. Master thesis comprise of folowing chapters: literature review, quality requirements, experimental, results and discusion, conclusions, references. Amount – 80 pages, 65 figures, 43 tables, 18 references.
Sinclair, Melissa Ann. "Modeling and Design of Antennas for Loosely Coupled Links in Wireless Power Transfer Applications." Thesis, University of North Texas, 2019. https://digital.library.unt.edu/ark:/67531/metadc1538705/.
Повний текст джерелаBeckmann, Bastian. "Additive manufacturing of hydraulic manifolds - a holistic approach across the entire value chain." Technische Universität Dresden, 2020. https://tud.qucosa.de/id/qucosa%3A71083.
Повний текст джерелаThompson, John Ryan. "RELATING MICROSTRUCTURE TO PROCESS VARIABLES IN BEAM-BASED ADDITIVE MANUFACTURING OF INCONEL 718." Wright State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=wright1401699643.
Повний текст джерелаKuntz, Sarah Louise. "Feasibility of Attaining Fully Equiaxed Microstructure through Process Variable Control for Additive Manufacturing of Ti-6Al-4V." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1464557846.
Повний текст джерелаAndriamiharivolamena, Fanamperana Tsitoha. "Contribution au développement d'antennes intégrables aux vêtements : application aux gilets militaires." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAT019/document.
Повний текст джерелаNowadays, the infantrymen of French army are equipped with a radio communication system when they are in field action. The antenna used to transmit and receive Radiofrequency (RF) signals is a monopole antenna called as whip antenna. It is placed parallel to the infantryman's body at the left clavicle. However, the whip antenna disrupts the field of view of infantrymen particularly when they turn their head to the left. Moreover, the position of the whip antenna bothers the left-handed infantrymen when they are in fire position. Finally, the whip antenna adds an additional weight to the infantrymen. Thus, it is obvious that the integration of the antenna into the military jackets allows to better meet the needs of infantrymen particularly in terms of ergonomy. However such an integration must also meet the needs in terms of radiation efficiency, spatial coverage and protection of the body against the antenna radiation. Moreover, the constraints of realization technology must be taken into account. The thesis is focused on the design and characterization of integrated antennas into military jackets. The research work is performed within the collaborative project GIANTE, supported by the DGA-RAPID frameproject, associating complementary partners: SAFRAN Sagem, laboratory LCIS, and ARDEJE. The work includes all the electromagnetic studies required by the environmental constraints by taking account the human body. It also includes the follow-up of the realizations made by ARDEJE that masters inkjet printing technologies. The RF characterization (impedance matching, bandwidth, radiation pattern) of antennas with a suitable bench test and the evaluation of global performances of antennas in functional environments (environment free from obstructions, urban areas, forest) are also part of the thesis work
Lin, Jiou-Wei, and 林久瑋. "3D metal powder printing sintering parameter studies." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/vbf7f7.
Повний текст джерела國立虎尾科技大學
機械與電腦輔助工程系碩士班
105
In the current industry, integrated manufacturing is highly competitive. As 3D printing continue to develop, the techniques and output value are also expending. In the present domestic market, 3D printing with PLA or ABS filament wires are the most common materials. Due to the low-cost and easy operation, the machine is often purchased by schools as a teaching tool. As for the metal 3D printing, it needs to insert protective gas in a closed off space, through laser sintering and stack-build to create an object with metal powder, although such techniques can produce complex parts, very few technical developments are found in the domestic market due to the high cost. The purpose of this study is to focus on the research of 3D metal powder sintering techniques and process. Through laser sintering experiments with different metal powder mixtures to confirm possible powder sintering, then use different laser power, scanning speeds, frequencies and path spacing parameters to conduct powder sintering experiments under different experimental conditions. By using optical microscope and Vickers Hardness tester to verify sintering products and using Taguchi method to find out best parameter combinations. The conclusions of the study are summarized as follow 1.In this study, the powder mixing mechanism was designed and used, the ratio of copper and tin powder for the mixing mechanism was 18: 1 2.If the scanning rate is higher than 30mm/s, the powder indicates insufficient temperature and shows a splash phenomenon which is not conducive to sintering. This will subsequently impact on the porosity and hardness analysis experiments. 3.Through Taguchi analysis, the best combine parameters for pore-space were found. The best pore-space is 4.712%, the laser power is 80%, and the scanning speed is 7mm/s, the frequency is 30k, and the path-space is 0.05mm. 4.Through Taguchi analysis, the best combine parameters for Vickers Hardness were found. The best pore-space is 134.423HV, the laser power is 100%, the scanning speed is 7mm/s, the frequency is 33K, and the path-space is 0.07mm.