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Additive manufacturing

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Full-Text Articles in Mechanical Engineering

Modeling Thermal And Mechanical Cancellation Of Residual Stress From Hybrid Additive Manufacturing By Laser Peening, Guru Madireddy, Chao Li, Jingfu Liu, Michael P. Sealy Jul 2019

Modeling Thermal And Mechanical Cancellation Of Residual Stress From Hybrid Additive Manufacturing By Laser Peening, Guru Madireddy, Chao Li, Jingfu Liu, Michael P. Sealy

Mechanical & Materials Engineering Faculty Publications

Additive manufacturing (AM) of metals often results in parts with unfavorable mechanical properties. Laser peening (LP) is a high strain rate mechanical surface treatment that hammers a workpiece and induces favorable mechanical properties. Peening strain hardens a surface and imparts compressive residual stresses improving the mechanical properties of a material. This work investigates the role of LP on layer-by-layer processing of 3D printed metals using finite element analysis. The objective is to understand temporal and spatial residual stress development after thermal and mechanical cancellation caused by cyclically coupling printing and peening. Results indicate layer peening frequency is a critical process ...


Evaluation Of Tensile Properties For Selective Laser Melted 316l Stainless Steel And The Influence Of Inherent Process Features, Paul Swartz Jun 2019

Evaluation Of Tensile Properties For Selective Laser Melted 316l Stainless Steel And The Influence Of Inherent Process Features, Paul Swartz

Master's Theses and Project Reports

Optimal print parameters for additively manufacturing 316L stainless steel using selective laser melting (SLM) at Cal Poly had previously been identified. In order to further support the viability of the current settings, tensile material characteristics were needed. Furthermore, reliable performance of the as-printed material had to be demonstrated. Any influence on the static performance of parts in the as-printed condition inherent to the SLM manufacturing process itself needed to be identified. Tensile testing was conducted to determine the properties of material in the as-printed condition. So as to have confidence in the experimental results, other investigations were also conducted to ...


A Hybrid Process Integrating Reverse Engineering, Pre-Repair Processing, Additive Manufacturing, And Material Testing For Component Remanufacturing, Xinchang Zhang, Wenyuan Cui, Wei Li, Frank W. Liou Jun 2019

A Hybrid Process Integrating Reverse Engineering, Pre-Repair Processing, Additive Manufacturing, And Material Testing For Component Remanufacturing, Xinchang Zhang, Wenyuan Cui, Wei Li, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Metallic components can gain defects such as dents, cracks, wear, heat checks, deformation, etc., that need to be repaired before reinserting into service for extending the lifespan of these parts. In this study, a hybrid process was developed to integrate reverse engineering, pre-repair processing, additive manufacturing, and material testing for the purpose of part remanufacturing. Worn components with varied defects were scanned using a 3D scanner to recreate the three-dimensional models. Pre-repair processing methods which include pre-repair machining and heat-treatment were introduced. Strategies for pre-repair machining of defects including surface impact damage, surface superficial damage and cracking were presented. Pre-repair ...


Mechanical Properties And Applications Of Recycled Polycarbonate Particle Material Extrusion-Based Additive Manufacturing, Matthew J. Reich, Aubrey Woern, Nagendra Gautam Tanikella, Joshua M. Pearce May 2019

Mechanical Properties And Applications Of Recycled Polycarbonate Particle Material Extrusion-Based Additive Manufacturing, Matthew J. Reich, Aubrey Woern, Nagendra Gautam Tanikella, Joshua M. Pearce

Michigan Tech Publications

Past work has shown that particle material extrusion (fused particle fabrication (FPF)/fused granular fabrication (FGF)) has the potential for increasing the use of recycled polymers in 3D printing. This study extends this potential to high-performance (high-mechanical-strength and heat-resistant) polymers using polycarbonate (PC). Recycled PC regrind of approximately 25 mm2 was 3D printed with an open-source Gigabot X and analyzed. A temperature and nozzle velocity matrix was used to find useful printing parameters, and a print test was used to maximize the output for a two-temperature stage extruder for PC. ASTM type 4 tensile test geometries as well as ...


A Study On Ultrasonic Energy Assisted Metal Processing : Its Correeltion With Microstructure And Properties, And Its Application To Additive Manufacturing., Anagh Deshpande May 2019

A Study On Ultrasonic Energy Assisted Metal Processing : Its Correeltion With Microstructure And Properties, And Its Application To Additive Manufacturing., Anagh Deshpande

Electronic Theses and Dissertations

Additive manufacturing or 3d printing is the process of constructing a 3-dimensional object layer-by-layer. This additive approach to manufacturing has enabled fabrication of complex components directly from a computer model (or a CAD model). The process has now matured from its earlier version of being a rapid prototyping tool to a technology that can fabricate service-ready components. Development of low-cost polymer additive manufacturing printers enabled by open source Fused Deposition Modeling (FDM) printers and printers of other technologies like SLA and binder jetting has made polymer additive manufacturing accessible and affordable. But the metal additive manufacturing technologies are still expensive ...


Nde In-Process For Metal Parts Fabricated Using Powder Based Additive Manufacturing, Leonard J. Bond, Lucas W. Koester, Hossein Taheri Mar 2019

Nde In-Process For Metal Parts Fabricated Using Powder Based Additive Manufacturing, Leonard J. Bond, Lucas W. Koester, Hossein Taheri

Aerospace Engineering Publications

Ensuring adequate quality for additive manufactured (AM) materials presents unique metrology challenges to the on-line process measurement and nondestructive evaluation (NDE) communities. AM parts now have complex forms that are not possible using subtractive manufacturing and there are moves for their use in safety criticality components. This paper briefly reviews the status, challenges and metrology opportunities throughout the AM process from powder to finished parts. The primary focus is on new acoustic signatures that have been demonstrated to correlate process parameters with on-line measurement for monitoring and characterization during the build. In-process, quantitative characterization and monitoring of material state is ...


Ultrafast X-Ray Imaging Of Laser-Metal Additive Manufacturing Processes, Niranjan D. Parab, Cang Zhao, Ross Cunningham, Luis I. Escano, Kamel Fezzaa, Wes Everhart, Anthony D. Rollett, Lianyi Chen, Tao Sun Jan 2019

Ultrafast X-Ray Imaging Of Laser-Metal Additive Manufacturing Processes, Niranjan D. Parab, Cang Zhao, Ross Cunningham, Luis I. Escano, Kamel Fezzaa, Wes Everhart, Anthony D. Rollett, Lianyi Chen, Tao Sun

Lianyi Chen

The high-speed synchrotron X-ray imaging technique was synchronized with a custom-built laser-melting setup to capture the dynamics of laser powder-bed fusion processes in situ. Various significant phenomena, including vapor-depression and melt-pool dynamics and powder-spatter ejection, were captured with high spatial and temporal resolution. Imaging frame rates of up to 10 MHz were used to capture the rapid changes in these highly dynamic phenomena. At the same time, relatively slow frame rates were employed to capture large-scale changes during the process. This experimental platform will be vital in the further understanding of laser additive manufacturing processes and will be particularly helpful ...


Additive Manufacturing Of Transparent Fused Quartz, Junjie Luo, John M. Hostetler, Luke Gilbert, Jonathan T. Goldstein, Augustine M. Urbas, Douglas A. Bristow, Robert G. Landers, Edward C. Kinzel Jan 2019

Additive Manufacturing Of Transparent Fused Quartz, Junjie Luo, John M. Hostetler, Luke Gilbert, Jonathan T. Goldstein, Augustine M. Urbas, Douglas A. Bristow, Robert G. Landers, Edward C. Kinzel

Douglas Bristow

This paper investigates a filament-fed process for additive manufacturing (AM) of fused quartz. Glasses such as fused quartz have significant scientific and engineering applications, which include optics, communications, electronics, and hermetic seals. AM has several attractive benefits such as increased design freedom, faster prototyping, and lower processing costs for small production volumes. However, current research into glass AM has focused primarily on nonoptical applications. Fused quartz is studied here because of its desirability for use in high-quality optics due to its high transmissivity and thermal stability. Fused quartz filaments are fed into a CO2 laser-generated molten region, smoothly depositing ...


An Energy Profile Model For Fused Deposition Modeling 3d Printing Process, Calvin Hawkins Jan 2019

An Energy Profile Model For Fused Deposition Modeling 3d Printing Process, Calvin Hawkins

ROEU 2018-19

This project develops a strategy to monitor and estimate the energy consumption of fused deposition modeling (FDM) additive manufacturing, which will benefit manufacturers and designers seeking to design and manufacture products with minimal energy consumption.


Mechanical Characterization Of Anisotropic Fused Deposition Modeled Polylactic Acid Under Combined Monotonic Bending And Torsion Conditions, Aaron T. Santomauro Jan 2019

Mechanical Characterization Of Anisotropic Fused Deposition Modeled Polylactic Acid Under Combined Monotonic Bending And Torsion Conditions, Aaron T. Santomauro

Honors Undergraduate Theses

Mechanical strength of polylactic acid (PLA) is increasingly relevant with time because of its attractive mechanical properties and 3D printability. Additive manufacturing (AM) methods, such as fused deposition modeling (FDM), stereolithography (SLA), and selective laser sintering (SLS), serve a vital role in assisting designers with cheap and efficient generation of the desired components. This document presents research to investigate the anisotropic response of multi-oriented PLA subjected to multiple monotonic loading conditions. Although empirical data has previously been captured for multi-oriented PLA under tensile and compressive loading conditions, the data has yet to be applied with regard to a representative component ...


Mechanical Performance Of Structural Systems With Missing Members: From Buildings To Architected Materials, Panagiotis Pantidis Jan 2019

Mechanical Performance Of Structural Systems With Missing Members: From Buildings To Architected Materials, Panagiotis Pantidis

Doctoral Dissertations

Structural systems are potentially subjected to damage initiating scenarios throughout the course of their service time. Depending on the nature and extent of the damaging event, they may experience significant reduction or even complete loss of their mechanical performance. This dissertation delves into the mechanics of structural systems under the notion of missing members from their domain, investigating types of structural systems: a) multi-story steel framed buildings, and b) materials with a truss-lattice microstructure.

Part I of the dissertation investigates the performance of multi-story steel framed buildings under a column removal scenario, developing an analytical framework for their quasi-static robustness ...


Rasters Vs Contours For Thin Wall Ultem 9085 Fdm Applications, Vausman Kota Jan 2019

Rasters Vs Contours For Thin Wall Ultem 9085 Fdm Applications, Vausman Kota

Browse all Theses and Dissertations

Currently many components are additively manufactured via fused deposition modeling (FDM). However, FDM results in gaps between passes which produces a poor surface finish and porous material that is difficult to hold pressure. Commercial scale air systems require a pressure to be maintained within thin walled components with minimal post processing and clean up after fabrication. A design of experiments (DOE) was created to identify the optimal raster vs contour ratio for UTLEM 9085 CG fabricated using FDM at different build angles and wall thicknesses. A custom-built pressurized test system was developed, the leak rates were calculated and the surfaces ...


Design And Mechanical Characterization Of 3d Printed Gradient Porosity Poly(Propylene Fumarate) Scaffolds, Andrea Felicelli Jan 2019

Design And Mechanical Characterization Of 3d Printed Gradient Porosity Poly(Propylene Fumarate) Scaffolds, Andrea Felicelli

Williams Honors College, Honors Research Projects

Worldwide incidence of bone disorders and conditions, an already prevalent problem, is expected to double by 2020 from the rate in 2013 due to factors such as higher life expectancies and lower levels of physical activity. Every year in the United States, over half a million patients receive bone defect repairs, with costs greater than $2.5 billion. Current repairs are typically done with bone grafts, which are often costly and can result in added complications in the donor surgical site. Tissue engineering, a growing field that seeks to assist and enhance tissue defect repairs through the use of synthetic ...


Freeform Extrusion Fabrication Of Advanced Ceramics And Ceramic-Based Composites, Wenbin Li Jan 2019

Freeform Extrusion Fabrication Of Advanced Ceramics And Ceramic-Based Composites, Wenbin Li

Doctoral Dissertations

"Ceramic On-Demand Extrusion (CODE) is a recently developed freeform extrusion fabrication process for producing dense ceramic components from single and multiple constituents. In this process, aqueous paste of ceramic particles with a very low binder content ( < 1 vol%) is extruded through a moving nozzle to print each layer sequentially. Once one layer is printed, it is surrounded by oil to prevent undesirable water evaporation from the perimeters of the part. The oil level is regulated just below the topmost layer of the part being fabricated. Infrared radiation is then applied to uniformly and partially dry the top layer so that the yield stress of the paste increases to avoid part deformation. By repeating the above steps, the part is printed in a layer-wise fashion, followed by post-processing. Paste extrusion precision of different extrusion mechanisms was compared and analyzed, with an auger extruder determined to be the most suitable paste extruder for the CODE system. A novel fabrication system was developed based on a motion gantry, auger extruders, and peripheral devices. Sample specimens were then produced from 3 mol% yttria stabilized zirconia using this fabrication system, and their properties, including density, flexural strength, Young's modulus, Weibull modulus, fracture toughness, and hardness were measured. The results indicated that superior mechanical properties were achieved by the CODE process among all the additive manufacturing processes. Further development was made on the CODE process to fabricate ceramic components that have external/internal features such as overhangs by using fugitive support material. Finally, ceramic composites with functionally graded materials (FGMs) were fabricated by the CODE process using a dynamic mixing device"--Abstract, page iv.


Glocal Integrity In 420 Stainless Steel By Asynchronous Laser Processing, Michael P. Sealy, Haitham Hadidi, Cody Kanger, X. L. Yan, Bai Cui, J. A. Mcgeough Jan 2019

Glocal Integrity In 420 Stainless Steel By Asynchronous Laser Processing, Michael P. Sealy, Haitham Hadidi, Cody Kanger, X. L. Yan, Bai Cui, J. A. Mcgeough

Mechanical & Materials Engineering Faculty Publications

Cold working individual layers during additive manufacturing (AM) by mechanical surface treatments, such as peening, effectively “prints” an aggregate surface integrity that is referred to as a glocal (i.e., local with global implications) integrity. Printing a complex, pre-designed glocal integrity throughout the build volume is a feasible approach to improve functional performance while mitigating distortion. However, coupling peening with AM introduces new manufacturing challenges, namely thermal cancellation, whereby heat relaxes favorable residual stresses and work hardening when printing on a peened layer. Thus, this work investigates glocal integrity formation from cyclically coupling LENS® with laser peening on 420 stainless ...


In Silico Analysis Of Advanced Processing Methods For Light-Weight Alloys Powders, Marjan Nezafati Dec 2018

In Silico Analysis Of Advanced Processing Methods For Light-Weight Alloys Powders, Marjan Nezafati

Theses and Dissertations

Light-weight Al and Mg-based metal-matrix nanocomposites (MMNCs) are lauded as one of the most promising structural materials for vehicle, military, and construction applications. These MMNCs are often synthesized using the powder metallurgy (PM) process under liquid nitrogen cryogenic environments to control the grain sizes. It is believed that proper incorporation of the nitrogen species into the bulk lattice during processing could strongly enhance the mechanical properties of MMNCs by forming N-rich dispersoids. In this work, using the density-functional theory (DFT), the adsorption, absorption and diffusion behavior of nitrogen molecule/atoms have been studied and related to t Al and Mg ...


Analysis Of Printed Electronic Adhesion, Electrical, Mechanical, And Thermal Performance For Resilient Hybrid Electronics, Clayton Neff Nov 2018

Analysis Of Printed Electronic Adhesion, Electrical, Mechanical, And Thermal Performance For Resilient Hybrid Electronics, Clayton Neff

Graduate Theses and Dissertations

Today’s state of the art additive manufacturing (AM) systems have the ability to fabricate multi-material devices with novel capabilities that were previously constrained by traditional manufacturing. AM machines fuse or deposit material in an additive fashion only where necessary, thus unlocking advantages of mass customization, no part-specific tooling, near arbitrary geometric complexity, and reduced lead times and cost. The combination of conductive ink micro-dispensing AM process with hybrid manufacturing processes including: laser machining, CNC machining, and pick & place enables the fabrication of printed electronics. Printed electronics exploit the integration of AM with hybrid processes and allow embedded and/or ...


Ultrafast X-Ray Imaging Of Laser-Metal Additive Manufacturing Processes, Niranjan D. Parab, Cang Zhao, Ross Cunningham, Luis I. Escano, Kamel Fezzaa, Wes Everhart, Anthony D. Rollett, Lianyi Chen, Tao Sun Sep 2018

Ultrafast X-Ray Imaging Of Laser-Metal Additive Manufacturing Processes, Niranjan D. Parab, Cang Zhao, Ross Cunningham, Luis I. Escano, Kamel Fezzaa, Wes Everhart, Anthony D. Rollett, Lianyi Chen, Tao Sun

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The high-speed synchrotron X-ray imaging technique was synchronized with a custom-built laser-melting setup to capture the dynamics of laser powder-bed fusion processes in situ. Various significant phenomena, including vapor-depression and melt-pool dynamics and powder-spatter ejection, were captured with high spatial and temporal resolution. Imaging frame rates of up to 10 MHz were used to capture the rapid changes in these highly dynamic phenomena. At the same time, relatively slow frame rates were employed to capture large-scale changes during the process. This experimental platform will be vital in the further understanding of laser additive manufacturing processes and will be particularly helpful ...


Finding Balance In Generative Product Design, Alex Lobos Aug 2018

Finding Balance In Generative Product Design, Alex Lobos

Presentations and other scholarship

Generative design develops complex forms and structures similar to those found in nature, taking advantage of automated tasks and high-scale computing power. This approach benefits designers in the creation systems that are efficient, resilient and visually engaging. These systems follow specific rules for form generation and meet clear design goals in terms of shape, strength, mass, and other physical attributes.

There is a large number of methods for creating generative systems, based on establishing desired outcomes and behaviors for how components relate to each other. Examples of methods include L-Systems, Shape Grammars, Swarm Intelligence, Form Optimization, Lattice Design, and many ...


Microstructure And Mechanical Properties Of Selective Laser Melted Superalloy Inconel 625., Md Ashabul Anam Aug 2018

Microstructure And Mechanical Properties Of Selective Laser Melted Superalloy Inconel 625., Md Ashabul Anam

Electronic Theses and Dissertations

Selective Laser Melting (SLM), a powder based Additive Manufacturing (AM) process, has gained considerable attention in the aerospace, biomedical and automotive industries due to its many potential benefits, such as, capability of fabricating complex three-dimensional components, shortened design to product time, reduction in process steps, component mass reduction and material flexibility. This process uses metallic powder and is capable of fabricating complex structures with excellent microstructure which make SLM not only an improvement over other manufacturing processes but also innovative material processing technology. Inconel 625, a nickel-based super alloy is widely popular in aerospace, chemical and nuclear industries. This alloy ...


Tooling For Injection Molding Using Laser-Powder Bed Fusion., Mohith Ram Buxani Jul 2018

Tooling For Injection Molding Using Laser-Powder Bed Fusion., Mohith Ram Buxani

Electronic Theses and Dissertations

Laser-Powder Bed Fusion (L-PBF) has been considered for some time by the injection molding industry for the fabrication of tooling for injection molding in order to address large lead times and costs for tool-making. Computer-aided simulations are also routinely used to evaluate new part and mold designs as well as understanding the effects of material compositions and processing conditions on part quality and overall productivity. However, there remains a significant need to integrate the perspectives from injection molding, 3D printing, metal powders, and component design and process simulation to better utilize LPBF for fabricating tooling required for injection molding. The ...


Additive Manufacturing Powder Removal, Madison A. Lignell, Tyler W. Laird, Kurt K. Reed Jun 2018

Additive Manufacturing Powder Removal, Madison A. Lignell, Tyler W. Laird, Kurt K. Reed

Mechanical Engineering

Metal powder-bed fusion is an additive manufacturing process which enables the creation of unique shapes in metal parts that would otherwise be difficult, expensive, or impossible to machine. Metallic powder is melted and fused together by either a laser or electron beam to produce parts quickly. The excess powder covers newly printed parts and can be difficult to remove from small internal features. The scope of this project is to design a device that effectively removes the powder from newly printed parts safely, while reclaiming as much powder as possible for reuse. The solution for this project must be able ...


Ultrasonic Nondestructive Evaluation Of Metal Additive Manufacturing., Venkata Karthik Nadimpalli May 2018

Ultrasonic Nondestructive Evaluation Of Metal Additive Manufacturing., Venkata Karthik Nadimpalli

Electronic Theses and Dissertations

Metal Additive Manufacturing (AM) is increasingly being used to make functional components. One of the barriers for AM components to become mainstream is the difficulty to certify them. AM components can have widely different properties based on process parameters. Improving an AM processes requires an understanding of process-structure-property correlations, which can be gathered in-situ and post-process through nondestructive and destructive methods. In this study, two metal AM processes were studied, the first is Ultrasonic Additive Manufacturing (UAM) and the second is Laser Powder Bed Fusion (L-PBF). The typical problems with UAM components are inter-layer and inter-track defects. To improve the ...


Modeling Residual Stress Development In Hybrid Processing By Additive Manufacturing And Laser Shock Peening, Guru Charan Reddy Madireddy Apr 2018

Modeling Residual Stress Development In Hybrid Processing By Additive Manufacturing And Laser Shock Peening, Guru Charan Reddy Madireddy

Mechanical (and Materials) Engineering -- Dissertations, Theses, and Student Research

The term “hybrid” has been widely applied to many areas of manufacturing. Naturally, that term has found a home in additive manufacturing as well. Hybrid additive manufacturing or hybrid-AM has been used to describe multi-material printing, combined machines (e.g., deposition printing and milling machine center), and combined processes (e.g., printing and interlayer laser re-melting). The capabilities afforded by hybrid-AM are rewriting the design rules for materials and adding a new dimension in the design for additive manufacturing paradigm. This work focuses on hybrid-AM processes, which are defined as the use of additive manufacturing (AM) with one or more ...


Additive Manufacturing Of High Solids Loading Hybrid Rocket Fuel Grains, Stephen P. Johnson Apr 2018

Additive Manufacturing Of High Solids Loading Hybrid Rocket Fuel Grains, Stephen P. Johnson

Scholar Week 2016 - present

Hybrid rocket motors offer many of the benefits of both liquid and solid rocket systems. Like liquid engines, hybrid rocket motors are able to be throttled, can be stopped and restarted, and are safer than solid rocket motors since the fuel and oxidizer are in different physical states. Hybrid rocket motors are similar to solid motors in that they are relatively simple and have a high density-specific impulse. One of the major drawbacks of hybrid rocket motors is a slower burning rate than solid rocket motors. Complex port geometries provide greater burning surface area to compensate for lower burning rates ...


Fabrication Of 3d Conjugated Polymer Structures Via Vat Polymerization Additive Manufacturing, Andrew T. Cullen Apr 2018

Fabrication Of 3d Conjugated Polymer Structures Via Vat Polymerization Additive Manufacturing, Andrew T. Cullen

Electronic Thesis and Dissertation Repository

Conjugated polymers are a class of electromechanically active materials that can produce motion in response to an electric potential. This motion can be harnessed to perform mechanical work, and therefore these materials are particularly well suited for use as sensors and actuators in microelectromechanical systems. Conventional methods to fabricate conjugated polymer actuators result in planar morphologies that limit fabricated devices to simplistic linear or bending actuation modes. To overcome this limitation, this work develops a conjugated polymer formulation and associated additive manufacturing method capable of realizing three-dimensional conductive polymer structures. A light-based additive manufacturing technique known as vat polymerization is ...


Additive Manufacturing Of Transparent Fused Quartz, Junjie Luo, John M. Hostetler, Luke Gilbert, Jonathan T. Goldstein, Augustine M. Urbas, Douglas A. Bristow, Robert G. Landers, Edward C. Kinzel Apr 2018

Additive Manufacturing Of Transparent Fused Quartz, Junjie Luo, John M. Hostetler, Luke Gilbert, Jonathan T. Goldstein, Augustine M. Urbas, Douglas A. Bristow, Robert G. Landers, Edward C. Kinzel

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper investigates a filament-fed process for additive manufacturing (AM) of fused quartz. Glasses such as fused quartz have significant scientific and engineering applications, which include optics, communications, electronics, and hermetic seals. AM has several attractive benefits such as increased design freedom, faster prototyping, and lower processing costs for small production volumes. However, current research into glass AM has focused primarily on nonoptical applications. Fused quartz is studied here because of its desirability for use in high-quality optics due to its high transmissivity and thermal stability. Fused quartz filaments are fed into a CO2 laser-generated molten region, smoothly depositing ...


Distributed Manufacturing Of Flexible Products: Technical Feasibility And Economic Viability, Aubrey Woern, Joshua M. Pearce Mar 2018

Distributed Manufacturing Of Flexible Products: Technical Feasibility And Economic Viability, Aubrey Woern, Joshua M. Pearce

Joshua M. Pearce

Distributed manufacturing even at the household level is now well established with the combined use of open source designs and self-replicating rapid prototyper (RepRap) 3-D printers. Previous work has shown substantial economic consumer benefits for producing their own polymer products. Now flexible filaments are available at roughly 3-times the cost of more conventional 3-D printing materials. To provide some insight into the potential for flexible filament to be both technically feasible and economically viable for distributed digital manufacturing at the consumer level this study investigates 20 common flexible household products. The 3-D printed products were quantified by print time, electrical ...


Impact Of Diy Home Manufacturing With 3d Printing On The Toy And Game Market, Emily Peterson, Joshua M. Pearce Mar 2018

Impact Of Diy Home Manufacturing With 3d Printing On The Toy And Game Market, Emily Peterson, Joshua M. Pearce

Joshua M. Pearce

The 2020 toy and game market is projected to be US$135 billion. To determine if 3D printing could affect these markets if consumers offset purchases by 3D printing free designs, this study investigates the 100 most popular downloaded designs at MyMiniFactory in a month. Savings are quantified for using a Lulzbot Mini 3D printer and three filament types: commercial filament, pellet-extruded filament, and post-consumer waste converted to filament with a recyclebot. Case studies probed the quality of: (1) six common complex toys; (2) Lego blocks; and (3) the customizability of open source board games. All filaments analyzed saved the ...


Selective Laser Melting Of Ni-Rich Niti: Selection Of Process Parameters And The Superelastic Response, Narges Shayesteh Moghaddam, Soheil Saedi, Amirhesam Amerinatanzi, Ehsan Saghaian, Ahmadreza Jahadakbar, Haluk E. Karaca, Mohammad Elahinia Mar 2018

Selective Laser Melting Of Ni-Rich Niti: Selection Of Process Parameters And The Superelastic Response, Narges Shayesteh Moghaddam, Soheil Saedi, Amirhesam Amerinatanzi, Ehsan Saghaian, Ahmadreza Jahadakbar, Haluk E. Karaca, Mohammad Elahinia

Mechanical Engineering Faculty Publications

Material and mechanical properties of NiTi shape memory alloys strongly depend on the fabrication process parameters and the resulting microstructure. In selective laser melting, the combination of parameters such as laser power, scanning speed, and hatch spacing determine the microstructural defects, grain size and texture. Therefore, processing parameters can be adjusted to tailor the microstructure and mechanical response of the alloy. In this work, NiTi samples were fabricated using Ni50.8Ti (at.%) powder via SLM PXM by Phenix/3D Systems and the effects of processing parameters were systematically studied. The relationship between the processing parameters and superelastic properties ...