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['Laboratory for Freeform Fabrication', 'University of Texas at Austin']
2018-04-10T15:54:05Z
2018-04-10T15:54:05Z
1990
Mechanical Engineering
doi:10.15781/T20R9MM7Z
http://hdl.handle.net/2152/64232
eng
1990 International Solid Freeform Fabrication Symposium
Open
['Laboratory for Freeform Fabrication', 'Annual International Solid Freeform Fabrication Symposium', 'Table of Contents']
1990 Annual International Solid Freeform Fabrication Symposium Table of Contents
Conference proceedings
https://repositories.lib.utexas.edu//bitstreams/05e27a82-99b2-45d1-a692-a248aeb63942/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T14:39:06Z
2022-08-23T14:39:06Z
1990
Mechanical Engineering
null
['https://hdl.handle.net/2152/115349', 'http://dx.doi.org/10.26153/tsw/42249']
eng
1990 International Solid Freeform Fabrication Symposium
Open
table of contents
1990 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/e75c0431-5a10-4b46-ad84-46a7bfe3f0a2/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T16:54:52Z
2022-08-23T16:54:52Z
1991
Mechanical Engineering
null
['https://hdl.handle.net/2152/115353', 'http://dx.doi.org/10.26153/tsw/42253']
eng
1991 International Solid Freeform Fabrication Symposium
Open
table of contents
1991 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/f3bfeae7-ecdd-4214-9c63-e3dd5cfd2bb2/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T16:56:10Z
2022-08-23T16:56:10Z
1992
Mechanical Engineering
null
['https://hdl.handle.net/2152/115354', 'http://dx.doi.org/10.26153/tsw/42254']
eng
1992 International Solid Freeform Fabrication Symposium
Open
table of contents
1992 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/ca3cc84d-3932-46b6-9bf0-10a43a0215a3/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T16:57:15Z
2022-08-23T16:57:15Z
1993
Mechanical Engineering
null
['https://hdl.handle.net/2152/115355', 'http://dx.doi.org/10.26153/tsw/42255']
eng
1993 International Solid Freeform Fabrication Symposium
Open
table of contents
1993 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/72119455-4ccd-4827-a74d-fba68589ed3a/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T16:58:01Z
2022-08-23T16:58:01Z
1994
Mechanical Engineering
null
['https://hdl.handle.net/2152/115356', 'http://dx.doi.org/10.26153/tsw/42256']
eng
1994 International Solid Freeform Fabrication Symposium
Open
table of contents
1994 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/cf9b9c26-2ab9-4c7a-a3f0-bfe34bb1ad12/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T16:59:05Z
2022-08-23T16:59:05Z
1995
Mechanical Engineering
null
['https://hdl.handle.net/2152/115357', 'http://dx.doi.org/10.26153/tsw/42257']
eng
1995 International Solid Freeform Fabrication Symposium
Open
table of contents
1995 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/4329961e-8534-4687-9f52-8f041bb18f6d/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T16:59:58Z
2022-08-23T16:59:58Z
1996
Mechanical Engineering
null
['https://hdl.handle.net/2152/115358', 'http://dx.doi.org/10.26153/tsw/42258']
eng
1996 International Solid Freeform Fabrication Symposium
Open
table of contents
1996 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/40fc45a9-1b4b-404a-9eff-dd1c6cdcc269/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:00:53Z
2022-08-23T17:00:53Z
1997
Mechanical Engineering
null
['https://hdl.handle.net/2152/115359', 'http://dx.doi.org/10.26153/tsw/42259']
eng
1997 International Solid Freeform Fabrication Symposium
Open
table of contents
1997 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/4eea6bbb-3d12-49bc-a9af-9227042aec85/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:01:47Z
2022-08-23T17:01:47Z
1998
Mechanical Engineering
null
['https://hdl.handle.net/2152/115360', 'http://dx.doi.org/10.26153/tsw/42260']
eng
1998 International Solid Freeform Fabrication Symposium
Open
table of contents
1998 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/6f2913d8-b81a-4a73-a3b2-619f617e5f22/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:02:48Z
2022-08-23T17:02:48Z
1999
Mechanical Engineering
null
['https://hdl.handle.net/2152/115361', 'http://dx.doi.org/10.26153/tsw/42261']
eng
1999 International Solid Freeform Fabrication Symposium
Open
['table of contents', 't']
1999 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/d353e0d0-0aaa-4b00-bc18-7bc86eed3032/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:06:19Z
2022-08-23T17:06:19Z
2000
Mechanical Engineering
null
['https://hdl.handle.net/2152/115362', 'http://dx.doi.org/10.26153/tsw/42262']
eng
2000 International Solid Freeform Fabrication Symposium
Open
table of contents
2000 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/6a3c1a7f-83ca-46af-a660-3528baa2ca87/download
null
null
null
null
null
null
null
null
International Solid Freeform Fabrication Symposium
2019-06-13T13:56:34Z
2019-06-13T13:56:34Z
2000
Mechanical Engineering
null
['https://hdl.handle.net/2152/74939', 'http://dx.doi.org/10.26153/tsw/2051']
eng
2000 International Solid Freeform Fabrication Symposium
Open
Eleventh Solid Freeform Fabrication (SFF) Symposium
2000 Preface
Conference paper
https://repositories.lib.utexas.edu//bitstreams/15e04d72-920f-4dd6-aaae-cdbd9c866e7b/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:07:35Z
2022-08-23T17:07:35Z
2001
Mechanical Engineering
null
['https://hdl.handle.net/2152/115363', 'http://dx.doi.org/10.26153/tsw/42263']
eng
2001 International Solid Freeform Fabrication Symposium
Open
table of contents
2001 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/6f8c99c1-c606-4d3e-9556-e21d2db217d2/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:09:06Z
2022-08-23T17:09:06Z
2002
Mechanical Engineering
null
['https://hdl.handle.net/2152/115364', 'http://dx.doi.org/10.26153/tsw/42264']
eng
2002 International Solid Freeform Fabrication Symposium
Open
table of contents
2002 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/e20ae9f5-d2da-43da-9ea6-ae6c6e966a60/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:10:34Z
2022-08-23T17:10:34Z
2003
Mechanical Engineering
null
['https://hdl.handle.net/2152/115365', 'http://dx.doi.org/10.26153/tsw/42265']
eng
2003 International Solid Freeform Fabrication Symposium
Open
table of contents
2003 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/69407420-e70d-409b-82e3-45cf08f61289/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:11:56Z
2022-08-23T17:11:56Z
2004
Mechanical Engineering
null
['https://hdl.handle.net/2152/115366', 'http://dx.doi.org/10.26153/tsw/42266']
eng
2004 International Solid Freeform Fabrication Symposium
Open
table of contents
2004 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/51061f27-b489-4f7d-a4e1-85ef7ee1b631/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:14:22Z
2022-08-23T17:14:22Z
2005
Mechanical Engineering
null
['https://hdl.handle.net/2152/115367', 'http://dx.doi.org/10.26153/tsw/42267']
eng
2005 International Solid Freeform Fabrication Symposium
Open
table of contents
2005 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/4011ba2d-357c-4894-991b-9d8c77e44816/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:15:55Z
2022-08-23T17:15:55Z
2006
Mechanical Engineering
null
['https://hdl.handle.net/2152/115368', 'http://dx.doi.org/10.26153/tsw/42268']
eng
2006 International Solid Freeform Fabrication Symposium
Open
table of contents
2006 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/f29f2722-e6c5-40b4-ac6b-3b57009ef0b7/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:17:26Z
2022-08-23T17:17:26Z
2007
Mechanical Engineering
null
['https://hdl.handle.net/2152/115369', 'http://dx.doi.org/10.26153/tsw/42269']
eng
2007 International Solid Freeform Fabrication Symposium
Open
table of contents
2007 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/65d3f831-0909-4c28-b78e-4a444eedbda2/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:18:39Z
2022-08-23T17:18:39Z
2008
Mechanical Engineering
null
['https://hdl.handle.net/2152/115370', 'http://dx.doi.org/10.26153/tsw/42270']
eng
2008 International Solid Freeform Fabrication Symposium
Open
table of contents
2008 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/09c22417-6b60-46ca-b396-49d3152d247f/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:20:00Z
2022-08-23T17:20:00Z
2009
Mechanical Engineering
null
['https://hdl.handle.net/2152/115371', 'http://dx.doi.org/10.26153/tsw/42271']
eng
2009 International Solid Freeform Fabrication Symposium
Open
table of contents
2009 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/1b9a7d9e-30db-4eae-930f-ed8924811bd7/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:21:01Z
2022-08-23T17:21:01Z
2010
Mechanical Engineering
null
['https://hdl.handle.net/2152/115372', 'http://dx.doi.org/10.26153/tsw/42272']
eng
2010 International Solid Freeform Fabrication Symposium
Open
table of contents
2010 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/e0adb26a-8a6a-4290-879f-b1e99a47d7b6/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:22:23Z
2022-08-23T17:22:23Z
2011
Mechanical Engineering
null
['https://hdl.handle.net/2152/115373', 'http://dx.doi.org/10.26153/tsw/42273']
eng
2011 International Solid Freeform Fabrication Symposium
Open
table of contents
2011 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/94bde5e9-2a8f-4162-b57b-072ff206423d/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:23:31Z
2022-08-23T17:23:31Z
2012
Mechanical Engineering
null
['https://hdl.handle.net/2152/115374', 'http://dx.doi.org/10.26153/tsw/42274']
eng
2012 International Solid Freeform Fabrication Symposium
Open
table of contents
2012 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/52f50796-dd3a-4553-ad69-fd6cbfbd9ea7/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:24:52Z
2022-08-23T17:24:52Z
2013
Mechanical Engineering
null
['https://hdl.handle.net/2152/115375', 'http://dx.doi.org/10.26153/tsw/42275']
eng
2013 International Solid Freeform Fabrication Symposium
Open
table of contents
2013 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/84cbabea-2091-41a4-89a8-98dee2468a78/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:26:12Z
2022-08-23T17:26:12Z
2014
Mechanical Engineering
null
['https://hdl.handle.net/2152/115376', 'http://dx.doi.org/10.26153/tsw/42276']
eng
2014 International Solid Freeform Fabrication Symposium
Open
table of contents
2014 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/cf72eabd-ec1d-43e2-b8b2-bf34cb3b3e5a/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:27:28Z
2022-08-23T17:27:28Z
2015
Mechanical Engineering
null
['https://hdl.handle.net/2152/115377', 'http://dx.doi.org/10.26153/tsw/42277']
eng
2015 International Solid Freeform Fabrication Symposium
Open
table of contents
2015 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/87232740-d486-4e83-8cc9-7082f1c2e09b/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:28:33Z
2022-08-23T17:28:33Z
2016
Mechanical Engineering
null
['https://hdl.handle.net/2152/115378', 'http://dx.doi.org/10.26153/tsw/42278']
eng
2016 International Solid Freeform Fabrication Symposium
Open
table of contents
2016 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/5a2bf1f8-5e38-49e7-b407-57a8cd4d6ad6/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-23T17:29:45Z
2022-08-23T17:29:45Z
2017
Mechanical Engineering
null
['https://hdl.handle.net/2152/115379', 'http://dx.doi.org/10.26153/tsw/42279']
eng
2017 International Solid Freeform Fabrication Symposium
Open
table of contents
2017 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/bc197195-896d-40da-b84e-fd90f0d10106/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-29T16:41:04Z
2022-08-29T16:41:04Z
2018
Mechanical Engineering
null
['https://hdl.handle.net/2152/115419', 'http://dx.doi.org/10.26153/tsw/42318']
eng
2018 International Solid Freeform Fabrication Symposium
Open
table of contents
2018 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/351ab080-bc01-403f-b38b-68a2531f2f13/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-29T16:43:07Z
2022-08-29T16:43:07Z
2019
Mechanical Engineering
null
['https://hdl.handle.net/2152/115420', 'http://dx.doi.org/10.26153/tsw/42319']
eng
2019 International Solid Freeform Fabrication Symposium
Open
table of contents
2019 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/d20e2a77-3afe-480b-bcdc-309bf272325b/download
null
null
null
null
null
null
null
null
Laboratory for Freeform Fabrication and University of Texas at Austin
2022-08-29T16:44:44Z
2022-08-29T16:44:44Z
2021
Mechanical Engineering
null
['https://hdl.handle.net/2152/115421', 'http://dx.doi.org/10.26153/tsw/42320']
eng
2021 International Solid Freeform Fabrication Symposium
Open
table of contents
2021 International Solid Freeform Fabrication Symposium Table of Contents
Other
https://repositories.lib.utexas.edu//bitstreams/e694c010-15df-40d1-ab03-ae5e1f98140e/download
null
null
null
null
null
null
null
null
University of Texas at Austin
2024-03-25T21:56:03Z
2024-03-25T21:56:03Z
2023
Mechanical Engineering
null
['https://hdl.handle.net/2152/124308', 'https://doi.org/10.26153/tsw/50916']
null
2023 International Solid Freeform Fabrication Symposium
Open
['preface', 'committee', '2023 Solid Freeform Fabrication Symposium']
2023 International Solid Freeform Fabrication Symposium Preface and Organizing Committee
Conference paper
https://repositories.lib.utexas.edu//bitstreams/7b8a6d7e-421c-4530-af41-a666a67e112d/download
University of Texas at Austin
null
null
null
null
null
null
null
['Roosendaal, Mark D. Van', 'Chamberlain, Peter', 'Thomas, Charles']
2019-02-26T16:27:06Z
2019-02-26T16:27:06Z
1998
Mechanical Engineering
null
['https://hdl.handle.net/2152/73481', 'http://dx.doi.org/10.26153/tsw/631']
eng
1998 International Solid Freeform Fabrication Symposium
Open
['Haar wavelet', 'Control variable']
2D Wavelet Analysis of Solid Objects: Applications in Layered Manufacturing
Conference paper
https://repositories.lib.utexas.edu//bitstreams/e7834ace-db27-4ee3-9cc8-6fa4767d8c63/download
null
In this paper, we introduce two-dimensional discrete wavelet basis functions and their application in the analysis and modeling ofsurface topography in layered manufacturing objects. In previous work, a one dimensional wavelet transform technique was developed to generate variable thickness layers. [1] For vertical edge layers Haar wavelet decomposition is used the slicing direction but is not useful in the slicing plane. For frequency analysis within the slicing plane, biorthogonal wavelets provide the desired analysis ability. When analyzing layered manufacturing with ruled edges a true 2-D transform is appropriate. Two-dimensional wavelet analysis simultaneously controls the layer thickness as well as the density of control points required the surface definition of each layer edge.
null
null
null
null
null
null
['Todd, J.A.', 'Copley, S.M.', 'Yankova, M.I.', 'Fariborzi, F.', 'West, K.']
2018-11-02T16:38:38Z
2018-11-02T16:38:38Z
1995
Mechanical Engineering
doi:10.15781/T2HQ3SJ0S
http://hdl.handle.net/2152/69338
eng
1995 International Solid Freeform Fabrication Symposium
Open
['CAD/CAM', 'polarization', 'beam power']
3-D Laser Shaping of Ceramic and Ceramic Composite Materials
Conference paper
https://repositories.lib.utexas.edu//bitstreams/0873ca49-b55b-4926-a47f-ae240fb6ec24/download
null
A versatile, automated, laser-based system, capable of producing complex threedimensional shapes of ceramic and ceramic composite materials, through either controlled layer ablation or solid freeform fabrication, is currently under development. The system comprises a 1.2 kW C021aser, positioning system, beam scanner, non-contacting positioning sensor, beam conditioner and CAD/CAM system. This paper reports progress in relating machine parameters (scan rate, feed, beam power and polarization) to process measurables (material removal rate and surface roughness), and demonstrates the potential for rapid prototyping and direct manufacturing of: (a) rotationally symmetric components based on ablative ceramics such as Si3N4 and (b) graphite fuel cell plenums
null
null
null
null
null
null
['Li, Xuxiao', 'Tan, Wenda']
2021-11-03T20:36:23Z
2021-11-03T20:36:23Z
2017
Mechanical Engineering
null
https://hdl.handle.net/2152/89926
eng
2017 International Solid Freeform Fabrication Symposium
Open
['grain structure', 'cellular automata', 'direct laser deposition', 'metal additive manufacturing']
3-Dimensional Cellular Automata Simulation of Grain Structure in Metal Additive Manufacturing Process
Conference paper
https://repositories.lib.utexas.edu//bitstreams/6bcb8670-a4ac-4b53-809c-04a1b04fbf9e/download
University of Texas at Austin
Distinct grain structures have been observed in Metal Additive Manufacturing (MAM) processes. These grain structures feature columnar grains which occasionally mix with equiaxed grains. The occurrence of these grain structures is not yet fully understood. In this work, direct laser deposition process is studied as a typical MAM process. A finite volume model is first implemented to obtain the thermal history. Next, the thermal history is fed into a Cellular Automata (CA) model to simulate the epitaxial and competitive growth through which the columnar grains are formed. Nucleation is included in the model to predict the generation of equiaxed grains, and is characterized by two nucleation parameters, the nucleation density and the critical undercooling. The simulation results show that both the nucleation parameters and process parameters can significantly affect the grain structure. The simulated grain structures examined on different planes can be significantly different, revealing the complexity of the 3-dimensional grain structures in MAM processes.
null
null
null
null
null
null
['Fu, C.H.', 'Guo, Y.B.']
2021-10-18T21:41:59Z
2021-10-18T21:41:59Z
2014
Mechanical Engineering
null
https://hdl.handle.net/2152/89257
eng
2014 International Solid Freeform Fabrication Symposium
Open
['selective laser melting', 'FEA', 'temperature gradient', 'molten pool']
3-Dimensional Finite Element Modeling of Selective Laser Melting Ti-6Al-4V Alloy
Conference paper
https://repositories.lib.utexas.edu//bitstreams/7797b9a1-095c-4a81-b8c8-0dc2b11db36b/download
University of Texas at Austin
Selective laser melting (SLM) is widely used in making three-dimensional functional parts layer by layer. Temperature magnitude and history during SLM directly determine the molten pool dimensions and surface integrity. However, due to the transient nature and small size of the molten pool, the temperature gradient and the molten pool size are very challenging to measure and control. A 3-dimensional finite element simulation model has been developed to simulate multi-layer deposition of Ti-6Al-4V in SLM. A physics-based layer build-up approach coupled with a surface moving heat flux was incorporated into the modeling process. The melting pool shape and dimensions were predicted and experimentally validated. Temperature gradient and thermal history in the multi-layer build-up process was also obtained. Furthermore, the influences of process parameters and materials on the melting process were evaluated.
null
null
null
null
null
null
['Sartin, B.', 'Pond, T.', 'Griffith, B.', 'Everhart, W.', 'Elder, L.', 'Wenski, E.', 'Cook, C.', 'Wieliczka, D.', 'King, W.', 'Rubenchik, A.', 'Wu, S.', 'Brown, B.', 'Johnson, C.', 'Crow, J.']
2021-11-02T15:25:08Z
2021-11-02T15:25:08Z
2017
Mechanical Engineering
null
https://hdl.handle.net/2152/89828
eng
2017 International Solid Freeform Fabrication Symposium
Open
['316L', 'metal powder', 'powder reuse', 'laser powder bed fusion', 'metal additive manufacturing']
316L Powder Reuse for Metal Additive Manufacturing
Conference paper
https://repositories.lib.utexas.edu//bitstreams/4f71b846-370b-4e74-bf89-9434938bf7c4/download
University of Texas at Austin
Metal additive manufacturing via laser powder bed fusion is challenged by low powder utilization. The ability to reuse metal powder will improve the process efficiency. 316L powder was reused twelve times during this study, completing thirty-one builds over one year and collecting 380 powder samples. The process, solidified samples, and powder were analyzed to develop an understanding of powder reuse implications. Solidified sample characteristics were affected more by slight process variations than by cycling of the powder. While a small percentage of powder was greatly affected by processing, the bulk powder only observed a slight increase in powder size.
null
null
null
null
null
null
['Xing, Juan', 'Luo, Xianli', 'Bermudez, Juliana', 'Moldthan, Matthew', 'Li, Bingbing']
2021-11-04T20:35:36Z
2021-11-04T20:35:36Z
2017
Mechanical Engineering
null
['https://hdl.handle.net/2152/90022', 'http://dx.doi.org/10.26153/16943']
eng
2017 International Solid Freeform Fabrication Symposium
Open
['scaffold structure', 'micro-extrusion', '3D bioprinting', '3D bioprinter']
3D Bioprinting of Scaffold Structure Using Micro-Extrusion Technology
Conference paper
https://repositories.lib.utexas.edu//bitstreams/e0865ee8-2284-43dd-bfbd-079e5c0109c8/download
University of Texas at Austin
Scaffold-based techniques are a vital assistance tool to support main structure and enhance the resolution of target structure. In this study, a custom-made micro-extrusion bioprinting system was built and utilized to fabricate different scaffold structures such as log-pile scaffold and two-ring scaffold. This approach showed tremendous potential because of its ability to produce microscale channels with almost any shape. We were able to fabricate these scaffolds by using a custom-made 3D bioprinter to print hydrogel solution, mostly composed of Pluronic F-127, then wash away hydrogen by phosphate buffer saline (PBS) after crosslinking of main structure. We were able to achieve the desired scaffold structure by feeding G-codes data into user interface (Pronterface) and then translating that model into a program that utilizes a customized programming language, which instructs the microfabrication printer nozzles to dispense the hydrogel at specific locations. This fundamental study will be used to print increasingly viable and complex tissue shapes with living cells.
null
null
null
null
null
null
['Saleh, E.', 'Vaithilingam, J.', 'Tuck, C.', 'Wildman, R.', 'Ashcroft, I.', 'Hague, R.', 'Dickens, P.']
2021-10-21T20:24:21Z
2021-10-21T20:24:21Z
2015
Mechanical Engineering
null
https://hdl.handle.net/2152/89438
eng
2015 International Solid Freeform Fabrication Symposium
Open
['3D inkjet printing', 'silver ink', 'conductive structures', 'IR sintering']
3D Inkjet Printing of Conductive Structures using In-Situ IR sintering
Conference paper
https://repositories.lib.utexas.edu//bitstreams/02e64cac-9e16-42fd-9088-9655aab4a854/download
University of Texas at Austin
In this study we investigate the inkjet printing of a silver nanoparticle ink and the optimization of IR sintering conditions to form 3D inkjet-printed conductive structures. The understanding of the interaction between the silver layers and the sintering conditions are key elements to successfully build conductive tracks in 3D. The drop size of conductive ink on glass substrates as well as on sintered conductive film was measured to optimize the printing resolution. The resistivity of the sintered deposition was studied in a planar X-Y direction as well as in a vertical Z direction to analyze the effects of stacking hundreds of silver layers in different deposition orientations. Using the results of the optimized printing and sintering conditions, conductive tracks were demonstrated forming simple 3D inkjet-printed structures powering electronic components.
null
null
null
null
null
null
['Aguiar, Daniel', 'Albuquerque, Amanda', 'Li, Bingbing']
2021-10-28T21:40:10Z
2021-10-28T21:40:10Z
2016
Mechanical Engineering
null
https://hdl.handle.net/2152/89707
eng
2016 International Solid Freeform Fabrication Symposium
Open
['bacterial cellulosic exopolysaccharide gel', 'droplet formation', '3D inkjetting', 'bioink', 'on-demand 3D printing', 'regenerative medicine']
3D Inkjetting Droplet Formation of Bacterial Cellulosic Exopolysaccharide Gel
Conference paper
https://repositories.lib.utexas.edu//bitstreams/56d89d3a-5aa8-4901-aeb7-39f7df83668f/download
University of Texas at Austin
On-demand 3D printing of scaffolds and cell-laden structures has shown promising results that can significantly impact human welfare. The objective is to fully understand the behavior of bacterial cellulosic exopolysaccharide gel (BCEG) as a new bioink with low toxicity and high biocompatibility for regenerative medicine. Its possible application is to construct scaffolds that can be used for several biomedical applications, especially tissue engineering and treatment of critical bone defects. By using a MicroFab inkjet micro dispenser, BCEG was dispersed to create drops on demand that can be used to fabricate scaffolds. In order to fully understand the material’s behavior and droplet formation, we analyzed the physical and mechanical properties of the BCEG in different concentrations (0.1% 0.5% and 1%) and characterized it by its macroscopy, microscopy, rheology and particle size distribution.
null
null
null
null
null
null
['Ederer, Ingo', 'Hochsmann, Rainer', 'Machan, Jurgen']
2018-10-05T17:26:22Z
2018-10-05T17:26:22Z
1995
Mechanical Engineering
doi:10.15781/T2VQ2SW00
http://hdl.handle.net/2152/68717
eng
1995 International Solid Freeform Fabrication Symposium
Open
['CAD', '3D Printing', 'UV Curable Resins']
A 3D Print Process For Inexpensive Plastic Parts
Conference paper
https://repositories.lib.utexas.edu//bitstreams/03db90e8-7800-4a64-a33a-b2fcf4c9e7be/download
null
Many of the currently available RP-Systems are suitable for building design models of arbitrarily shaped parts. However, most of these RP processes use sophisticated and expensive equipment which is not well suited for an office environment. In this paper we present a method and an experimental device for building design models by a modified 3D print process using plastic powder and a photopolymeric binder.
null
null
null
null
null
null
['Lipton, Jeffrey Ian', 'Angle, Sarah', 'Lipson, Hod']
2021-10-18T20:11:06Z
2021-10-18T20:11:06Z
2014
Mechanical Engineering
null
https://hdl.handle.net/2152/89228
eng
2014 International Solid Freeform Fabrication Symposium
Open
['wax', 'actuator', 'robocasting']
3D Printable Wax-Silicone Actuators
Conference paper
https://repositories.lib.utexas.edu//bitstreams/24111e76-38bd-405e-9c76-3be29d7fad4f/download
University of Texas at Austin
The Solid Freeform Fabrication of actuators has been an area of active development. So far only weak polymer actuators, or small displacement piezoelectric, and pneumatic actuators have been produced. We developed a novel material platform of silicone and wax which can be used to make soft actuators that are thermally activated. The material is made by mechanically mixing liquid silicone and liquid paraffin wax and cooled to create a suspension of wax particles suspended in a silicone liquid. The resulting material expands by up to 6% of volume when heated above the wax melting temperature.
null
null
null
null
null
null
['Bowa, M.', 'Dean, M.E.', 'Horn, R.D.']
2021-11-15T22:12:40Z
2021-11-15T22:12:40Z
2018
Mechanical Engineering
null
['https://hdl.handle.net/2152/90289', 'http://dx.doi.org/10.26153/tsw/17210']
eng
2018 International Solid Freeform Fabrication Symposium
Open
['3D printed electronics', '3D printing', 'additive manufacturing', 'sustainability', 'cost effectiveness']
3D Printed Electronics
Conference paper
https://repositories.lib.utexas.edu//bitstreams/bd23a633-415a-4d98-a800-3508d6414594/download
University of Texas at Austin
Additive manufacturing is revolutionizing the way we build and produce a plethora of products spanning many industries. It has shown strong potential in reduced energy use, sustainability and cost effectiveness. Exploring avenues that this technology can be utilized is key to improve productivity and efficiencies in various applications including electronic systems and devices manufacturing. Electronic systems and sub-systems are built using a variety of material and processes, which require a large carbon footprint, significant waste material and high production time. We propose the application of 3D printing technology to support an integrative process for combining circuit board fabrication, solder mask process, electronic component pick and place and enclosure manufacturing. The integration of these separate processes into a single high efficiency additive manufacturing process will yield significant savings in energy use, carbon footprint, waste product and production time and cost.
null
null
null
null
null
null
['Delgado Camacho, Daniel', 'Clayton, Patricia', "O'Brien, William J.", 'Jung, Kee Young']
2021-11-09T19:27:34Z
2021-11-09T19:27:34Z
2018
Mechanical Engineering
null
['https://hdl.handle.net/2152/90141', 'http://dx.doi.org/10.26153/tsw/17062']
eng
2018 International Solid Freeform Fabrication Symposium
Open
['fastener-free connections', 'additive manufacturing', '3D printing', 'material extrusion', 'polymers', 'flexural test']
3D Printed Fastener-Free Connections for Non-Structural and Structural Applications – An Exploratory Investigation
Conference paper
https://repositories.lib.utexas.edu//bitstreams/b6af235f-8e6e-424c-92d3-0560a1fc51c6/download
University of Texas at Austin
The construction industry has shown increasing interest in AM technologies and has successfully implemented various proof of concept projects using different AM processes. Much of the research on AM in the construction industry has focused on development of new large-scale extrusion printing systems and on development of cementitious materials for AM applications, whereas research exploring new applications of already existing AM technologies and materials suitable for construction applications has been scarce. This paper explores the use of existing, small-scale material extrusion 3D printers to create fastener-free connections that could be used in structural or non-structural applications. These connections, inspired by traditional wood joinery and modern proprietary connections were printed using polylactic acid (PLA) material. The flexural strength of the connections was then tested using a four-point bending test to evaluate their potential structural performance and to identify connection types that warrant further research in this exploratory proof of concept study.
null
null
null
null
null
null
['Emery, B.A.', 'Revier, D.', 'Sarkar, V.', 'Nakura, M.', 'Lipton, J. I.']
2024-03-27T03:25:11Z
2024-03-27T03:25:11Z
2023
Mechanical Engineering
null
['https://hdl.handle.net/2152/124464', 'https://doi.org/10.26153/tsw/51072']
en_US
2023 International Solid Freeform Fabrication Symposium
Open
['viscous thread printing', 'additive manufacturing', 'foam', 'stiffness']
3D Printed Intelligently Graded Functional Stiffness Foam for Sturdier Multi Stiffness Materials
Conference paper
https://repositories.lib.utexas.edu//bitstreams/b79a6530-9f60-453e-876a-710f992d0ad5/download
University of Texas at Austin
Foams are ubiquitous, being used in applications such as padding, insulation, and noise isolation. Bonding different density foams together produces undesired stress concentrations and boundary effects. Creating controlled gradients in foam properties has been a challenge for traditional and AM processes. Here we show how to use a form of material extrusion called Viscous Thread APrinting (VTP) to produce foams with multiple stiffnesses and continuous gradients between different stiffnesses. We do so by varying the path speed during extrusion to control the production of microstructures. We compare the process of producing discrete components and those with gradients, showing that those with gradients have higher strength in plane during tension, have no discontinuities in out of plane stiffness, and are less prone to forming cracks at the boundaries. We demonstrate the process in thermoplastic polyurethane (TPU).
null
null
null
null
null
null
['Bryant, Nathaniel', 'Villela, Janely', 'Villela, Juan Owen', 'Alemán, Alan', 'O’Dell, Josh', 'Ravi, Sairam', 'Thiel, Jerry', 'MacDonald, Eric']
2023-01-31T14:14:39Z
2023-01-31T14:14:39Z
2022
Mechanical Engineering
null
['https://hdl.handle.net/2152/117368', 'http://dx.doi.org/10.26153/tsw/44249']
eng
2022 International Solid Freeform Fabrication Symposium
Open
['Additive manufacturing', '3D Printed Sand Casting', 'Binder jetting', 'Curing']
3D Printed Smart Mold for Sand Casting: Monitoring Pre-Pour Binder Curing
Conference paper
https://repositories.lib.utexas.edu//bitstreams/d8799ddb-6f71-4370-8f2b-4d22dc45f35e/download
null
The benefits of additive manufacturing for fabricating complex sacrificial sand molds for geometrically-complex metal castings is revolutionizing the foundry industry driven by a digital manufacturing paradigm. The design freedom of 3D printing allows for new mold designs - not possible with traditional approaches - such as helical sprues, varying wall thickness to tailor the thermal history, and spatially-varying lattice castings. However, research on the curing time of printed molds, including the aging of printed molds, requires more exploration. This study describes the experimental evaluation of 3D printed specimens in which embedded environmental sensors were fully encapsulated into sand blocks during an interruption of the binder jetting process. Subsequently, over a 28 day duration, humidity, volatile organic compound generation, temperature and barometric pressure were captured for three environmental treatments. Mechanical testing of standard test specimens subjected to the same conditions was conducted. The sand structures held in high (uncontrolled) humidity and at reduced temperature were statistically significantly weaker than a third treatment based on the hypothesis that high humidity and/or low temperatures impede curing. The use of embedded sensors could provide guidelines for mold and core storage conditions as well as in high-value production to inform the minimum (for full curing) and maximum duration (mold expiration) after printing to identify the optimal time to pour metal during the life of a printed sand mold.
null
null
null
null
null
null
['Bryant, Nathaniel', 'Villela, Janely', 'Villela, Juan Owen', 'Alemán, Alan', 'O’Dell, Josh', 'Ravi, Sairam', 'Thiel, Jerry', 'MacDonald, Eric']
2023-01-27T18:08:23Z
2023-01-27T18:08:23Z
2022
Mechanical Engineering
null
['https://hdl.handle.net/2152/117354', 'http://dx.doi.org/10.26153/tsw/44235']
eng
2022 International Solid Freeform Fabrication Symposium
Open
['Additive manufacturing', '3D Printed Sand Casting', 'Binder Jetting', 'Curing']
3D Printed Smart Mold for Sand Casting: Monitoring Pre-Pour Binder Curing
Conference paper
https://repositories.lib.utexas.edu//bitstreams/cb79f2dd-3610-4b68-94f4-6ad603777cee/download
null
The benefits of additive manufacturing for fabricating complex sacrificial sand molds for geometrically-complex metal castings is revolutionizing the foundry industry driven by a digital manufacturing paradigm. The design freedom of 3D printing allows for new mold designs - not possible with traditional approaches - such as helical sprues, varying wall thickness to tailor the thermal history, and spatially-varying lattice castings. However, research on the curing time of printed molds, including the aging of printed molds, requires more exploration. This study describes the experimental evaluation of 3D printed specimens in which embedded environmental sensors were fully encapsulated into sand blocks during an interruption of the binder jetting process. Subsequently, over a 28 day duration, humidity, volatile organic compound generation, temperature and barometric pressure were captured for three environmental treatments. Mechanical testing of standard test specimens subjected to the same conditions was conducted. The sand structures held in high (uncontrolled) humidity and at reduced temperature were statistically significantly weaker than a third treatment based on the hypothesis that high humidity and/or low temperatures impede curing. The use of embedded sensors could provide guidelines for mold and core storage conditions as well as in high-value production to inform the minimum (for full curing) and maximum duration (mold expiration) after printing to identify the optimal time to pour metal during the life of a printed sand mold.
null
null
null
null
null
null
['Munguia, J.', 'Honey, T.', 'Zhang, Y.', 'Drinnan, M.', 'Di Maria, C.', 'Bray, A.', 'Withaker, M.']
2021-10-28T21:37:15Z
2021-10-28T21:37:15Z
2016
Mechanical Engineering
null
https://hdl.handle.net/2152/89705
eng
2016 International Solid Freeform Fabrication Symposium
Open
['3D printing', 'home-use medical device', 'redistributed manufacturing']
3D Printing Enabled-Redistributed Manufacturing of Medical Devices
Conference paper
https://repositories.lib.utexas.edu//bitstreams/4fc126ef-f044-47a6-b46b-1fec5a5519b3/download
University of Texas at Austin
Recently the home-use segment of medical devices has entered in the loop of Additive Manufacturing (AM) enabled optimizations, this includes CPAP masks, insulin delivery packs and diagnostic tools such as urine-flow meters. Here we analyze the supply chain provision of a specific uroflowmetry device which is originally designed in Europe, manufactured in Asia and which has a range of distribution channels across healthcare systems. This paper analyses the impact of various AM technologies that can enable near-patient manufacture of devices on-demand. Our analysis shows that the cost of design-changes (or product updates), when reflected on the overall lifecycle cost, can be comparable to producing the device locally with a different supply chain arrangement. Furthermore it is suggested that in order to fully exploit the capabilities afforded by AM, the original product’s design features must be modified so that built-times are reduced allowing a larger 3D printing-based production capacity.
null
null
null
null
null
null
['McDonnell, Bill', 'Jimenez Guzman, Xavier', 'Dolack, Matthew', 'Simpson, Timothy W.', 'Cimbala, John M.']
2021-11-01T22:53:23Z
2021-11-01T22:53:23Z
2016
Mechanical Engineering
null
https://hdl.handle.net/2152/89789
eng
2016 International Solid Freeform Fabrication Symposium
Open
['volatile organic compounds', 'particulate matters', 'air quality', 'maker spaces', 'college', '3D printing']
3D Printing in the Wild: A Preliminary Investigation of Air Quality in College Maker Spaces
Conference paper
https://repositories.lib.utexas.edu//bitstreams/a78b490b-10b0-46a1-b44f-d2eafb2e3c79/download
University of Texas at Austin
Additive manufacturing is a popular method for prototyping and manufacturing custom parts, especially on college campuses. While there is widespread use of 3D printers as part of many engineering classwork, there is little regulation or knowledge regarding emissions. Many plastics, including polycarbonates, ABS, and PLA are known to emit high counts of volatile organic compounds (VOCs) and particulate matters (PMs). This study focuses on VOC and PM counts in several natural environments and dedicated “maker spaces” on a large college campus to gauge the exposure that students and operators experience. Emissions were measured using a photoionization detector and two particle sizers. The photoionization detector measured total VOCs, and the particle size counters measured both total nanoparticles and individual micro-particles based on relative particle diameter. Measurements were taken in hourly increments and then analyzed to determine the degree with which desktop printers emitted VOCs and PM. Our data can be used to determine whether additional ventilation or filtration is needed when 3D printing “in the wild” to enhance operator and bystander safety.
null
null
null
null
null
null
['Murphy, C.', 'Kolan, K.C.R.', 'Long, M.', 'Li, W.', 'Leu, M.C.', 'Semon, J.A.', 'Day, D.E.']
2021-10-28T21:55:10Z
2021-10-28T21:55:10Z
2016
Mechanical Engineering
null
https://hdl.handle.net/2152/89710
eng
2016 International Solid Freeform Fabrication Symposium
Open
['AD-MSCs', 'polycaprolactone', 'bioactive glass', '3D printing', 'bone repair']
3D Printing of a Polymer Bioactive Glass Composite for Bone Repair
Conference paper
https://repositories.lib.utexas.edu//bitstreams/4cffd082-c827-4f49-950a-a53a64465504/download
University of Texas at Austin
A major limitation of synthetic bone repair is insufficient vascularization of the interior region of the scaffold. In this study, we investigated the 3D printing of adipose derived mesenchymal stem cells (AD-MSCs) with polycaprolactone (PCL)/bioactive glass composite in a single process. This offered a three-dimensional environment for complex and dynamic interactions that govern the cell’s behavior in vivo. Borate based bioactive (13-93B3) glass of different concentrations (10 to 50 weight %) was added to a mixture of PCL and organic solvent to make an extrudable paste. AD-MSCs suspended in Matrigel was extruded as droplets using a second syringe. Scaffolds measuring 10x10x1 mm3 in overall dimensions with a filament width of ~500 µm and pore sizes ranging from 100 to 200 µm were fabricated. Strut formability dependence on paste viscosity, scaffold integrity, and printing parameters for droplets of ADMSCs suspended in Matrigel were investigated.
null
null
null
null
null
null
['Phillips, Tim', 'Allison, Jared', 'Beaman, Joseph']
2024-03-27T03:27:15Z
2024-03-27T03:27:15Z
2023
Mechanical Engineering
null
['https://hdl.handle.net/2152/124465', 'https://doi.org/10.26153/tsw/51073']
en_US
2023 International Solid Freeform Fabrication Symposium
Open
['additive manufacturing', '3D printing', 'resistance response', 'stress response']
3D Printing of Complex Wire Geometries for Tailored Resistance Response
Conference paper
https://repositories.lib.utexas.edu//bitstreams/89a5c9bd-8585-4111-af04-506c11fa307f/download
University of Texas at Austin
Additive manufacturing (AM) is a rapidly growing field that enables production of complex geometries without tooling. AM has gained traction as a method of producing complex electronic circuits not possible using traditional techniques. The method explored in this manuscript involves post-build infiltration of conductive inks into complex channels to create resistive elements with tunable properties. A Polyjet printer is used to enable high-precision multimaterial components with custom mechanical properties. Further, the conductive pathway geometry can be designed to achieve different resistive responses. These properties allow for decoupling of the stress-strain response and resistance-strain response to produce custom strain gauges with engineered properties.
null
null
null
null
null
null
['Jayashankar, Dhileep Kumar', 'Gupta, Sachin Sean', 'Stella, Loo Yi Ning', 'Tracy, Kenneth']
2021-11-18T02:09:59Z
2021-11-18T02:09:59Z
2019
Mechanical Engineering
null
['https://hdl.handle.net/2152/90409', 'http://dx.doi.org/10.26153/tsw/17330']
eng
2019 International Solid Freeform Fabrication Symposium
Open
['compliant mechanism', 'passive actuation', 'additive manufacturing', 'chitosan biopolymer']
3D Printing of Compliant Passively Actuated 4D Structures
Conference paper
https://repositories.lib.utexas.edu//bitstreams/204bad6d-fc3e-4435-bc6d-2577224c7bd3/download
University of Texas at Austin
Additive manufacturing has begun to revolutionize the production of various physical technologies that depend on bespoke geometry and tailored material properties for function. This includes the design of compliant mechanisms, which rely on an integral coupling between geometric and material parameters to attain the elastic flexibility necessary to accommodate programmed deformation. While kinetic structures with compliant parts are typically activated by the application of a mechanical force, alternative means of achieving motion are available, such as the use of smart, 4D, or stimuli-responsive materials which react to environmental conditions. In this research, a combination of compliant mechanisms and water-responsive chitosan biopolymers was explored to create flexible, programmable passive actuators, enabled by 3D printing. A set of compliant joints were modeled, simulated, fabricated, and tested to determine the optimal design for use in the actuator. The actuator was then iteratively tested with wetting and drying of chitosan films to invoke a specific shape change, which was analyzed for accuracy, speed, and consistency. The study concluded with a discussion of the implications of synthesizing compliant mechanisms, chitosan biopolymer, and additive manufacturing for next-generation adaptive structures.
null
null
null
null
null
null
['Aguilera, Efrain', 'Ramos, Jorge', 'Espalin, David', 'Cedillos, Fernando', 'Muse, Dan', 'Wicker, Ryan', 'MacDonald, Eric']
2021-10-12T18:28:39Z
2021-10-12T18:28:39Z
2013
Mechanical Engineering
null
['https://hdl.handle.net/2152/88715', 'http://dx.doi.org/10.26153/tsw/15649']
eng
2013 International Solid Freeform Fabrication Symposium
Open
['Additive Manufacturing', '3D printed electronics', '3D printed electromechanical devices', 'hybrid manufacturing', 'structural electronics']
3D Printing of Electro Mechanical Systems
Conference paper
https://repositories.lib.utexas.edu//bitstreams/69e0bbf6-0b76-4137-be71-e87f225476cb/download
University of Texas at Austin
Recent research has focused on the fabrication freedom of 3D printing to not only create conceptual models but final end-use products as well. By democratizing the manufacturing process, products will inevitably be fabricated locally and with unit-level customization. For 3D printed end-use products to be profoundly meaningful, the fabrication technologies will be required to enhance the structures with additional features such as electromechanical content. In the last decade, several research groups have reported embedding electronic components and electrical interconnect into 3D printed structures during process interruptions. However, to date there appears to be an absence of fabricated devices with electromechanical functionality in which moving parts with electronic control have been created within a single Additive Manufacturing (AM) build sequence. Moreover, previously reported 3D printed electronics were limited by the use of conductive inks, which serve as electrical interconnect and are commonly known for inadequate conductivity. This paper describes the fabrication of a high current (>1 amp) electromechanical device through a single hybrid AM build sequence using a uPrint Plus, a relatively low cost 3D. Additionally, a novel integrated process for embedding high performance conductors directly into the thermoplastic FDM substrate is demonstrated. By avoiding low conductivity inks, high power electromechanical applications are enabled such as 3D printed robotics, UAVs and biomedical devices.
null
null
null
null
null
null
Mohammed, Mazher Iqbal
2024-03-27T03:29:18Z
2024-03-27T03:29:18Z
2023
Mechanical Engineering
null
['https://hdl.handle.net/2152/124466', 'https://doi.org/10.26153/tsw/51074']
en_US
2023 International Solid Freeform Fabrication Symposium
Open
['additive manufacturing', 'microfluidics', '3D printing']
3D Printing of Passive Microfluidic Flow Mixers Using Triply Period Minimal Surface Microlattice Structures
Conference paper
https://repositories.lib.utexas.edu//bitstreams/eb5d7ce9-7d6b-43fb-8fb3-51070148af86/download
University of Texas at Austin
Microfluidics are miniaturised devices useful for precision fluid handling phases when conducting a range of chemical reactions or biological processes. Such devices operate at micrometre length scales, where laminar flow dominates and so interactions are limited to diffusion between the flowing liquid interfaces unless flow is made turbulent to induce mixing. Passive mixers are desirable for this task as they comprise geometrical features which can be incorporated during the fabrication of such devices. Designs largely remain planar due to traditional microfluidic manufacturing being conducted with 2.5D fabrication processes. Additive Manufacturing now allows for passive mixers to now be realised in true 3D but have seen limited investigation. This study explores the efficacy of several miniaturised Triply Period Minimal Surface micro-lattice structures, formed within microfluidic channels as turbulence inducing structures for increased mixing. We explore several lattice designs and report on their efficacy for mixing reactions conducted during continuous flow conditions.
null
null
null
null
null
null
['Kantareddy, S.N.R.', 'Simpson, T.W.', 'Ounaies, Z.', 'Frecker, M.']
2021-11-01T21:51:42Z
2021-11-01T21:51:42Z
2016
Mechanical Engineering
null
https://hdl.handle.net/2152/89768
eng
2016 International Solid Freeform Fabrication Symposium
Open
['shape memory polymers', 'shape changing polymers', '3D printing', 'additive manufacturing']
3D Printing of Shape Changing Polymer Structures: Design and Characterization of Materials
Conference paper
https://repositories.lib.utexas.edu//bitstreams/9fc3e69b-ed82-4002-9dc0-d58e4bcc258d/download
University of Texas at Austin
Additive manufacturing (AM) gives engineers unprecedented design and material freedom, providing the ability to 3D print polymer structures that can change shape. Many of these Shape Memory Polymer (SMP) structures require multi-material composites, and different programmed shapes can be achieved by designing and engineering these composites to fold and unfold at different rates. To enable SMP applications involving shape-changing geometries, it is important to have an understanding of the relationships between intermediate shapes and the initial and final designed shapes. To accomplish this, we investigated readily available 3D printable polymer materials and their thermo-mechanical characteristics to create multi-member structures. This paper demonstrates a way to generate different temporary geometric profiles on a single 3D printed shape with the same material. This paper also includes insights from thermo-mechanical analysis of the materials to help create multi-member shape-changing geometries using 3D printing.
null
null
null
null
null
null
['Chang, Shawn H.', 'Moser, Bryan R.']
2021-11-01T20:46:33Z
2021-11-01T20:46:33Z
2016
Mechanical Engineering
null
https://hdl.handle.net/2152/89743
eng
2016 International Solid Freeform Fabrication Symposium
Open
['additive manufacturing', '3D printing', 'technology insertion', 'sociotechnical systems']
3D Printing Technology Insertion: Sociotechnical Barriers to Adoption
Conference paper
https://repositories.lib.utexas.edu//bitstreams/c8bb7aac-1309-4ff7-84ab-131069a5f725/download
University of Texas at Austin
Since the initial development of three dimensional printing (3DP) in the 1980s, companies have relentlessly researched for applications of the technology. The potential benefit is large, beginning with improved cost and schedule to manufacture plastic and metal articles. As such, governments and industry from advanced economies continue to invest heavily to accelerate 3DP adoption. Amid advancements in the pillars of three dimensional printing – the technology, material, and software – practitioners across industries are steadily deploying 3DP in product development, prototyping, and small scale production of parts and products. However, a large gap remains between promise and the reality of larger scale adoption. The potential benefits, risks, and specific steps to adopt and realize the benefits are not clearly understood, resulting in overly zealous (at risk) or overly cautious (opportunity avoided) approaches to 3DP adoption. Traditional manufacturers rely on decades of know-how in manufacturing practices across a large portfolio of parts, making first steps on a path to adopt new processes more challenging. This paper identifies the variables that complicate or impair judgement when considering the adoption of 3DP. A systematic approach to evaluate 3DP adoption across a portfolio is needed. A methodology is proposed to analyze the relative value of 3DP at the part and product system level for prototyping and production. The outcome is a framework that combines part-level feasibility with systemic benefit of cost and schedule improvements as prototyping and production alternatives. In building this framework and in interviews with experienced manufacturers, several key insights were gained. Part by part consideration of 3DP feasibility is daunting, while adoption requires readiness not only of 3DP technology but also the receiving systems and organization. By viewing 3DP insertion as a sociotechnical system implementing the changes, attention is drawn to the tacit knowledge of critical characteristics in existing manufacturing processes, design for manufacturing decisions embedded in existing part assemblies, the pre-processing and post-processing capabilities available to shift 3DP feasibilities, and the alignment of organizational learning across parts.
null
null
null
null
null
null
Fly, David E.
2021-10-18T20:05:10Z
2021-10-18T20:05:10Z
2014
Mechanical Engineering
null
https://hdl.handle.net/2152/89225
eng
2014 International Solid Freeform Fabrication Symposium
Open
['composites', 'strength-to-weight ratio', 'additive manufacturing', '3D printing']
3D Printing Thin Skinned Composites to Achieve the Strength-to-Weight Ratio of Aluminum
Conference paper
https://repositories.lib.utexas.edu//bitstreams/117ac7a1-b284-494b-bcb1-017b5f6eb164/download
University of Texas at Austin
Kevlar and stainless steel mesh reinforcements were added using epoxy to 3D printed ABS-M30 thin skins, thereby making a composite structure with significantly improved mechanical properties over that of the 3D printed plastic alone. These additive manufactured composites have a strength to weight ratio that is comparable to solid aluminum. Flexural 3-point bend tests and Charpy Impact tests were conducted. Experiments were conducted that were designed to characterize the influence of adding Kevlar to the composite structure and also the influence of pre-mixing glass microspheres into the epoxy. These new additive manufactured (AM) composites are an attractive choice to designers attempting to reduce weight because any 3D printed shape can be reinforced in this manner. Additionally, actual production time is less than 3D printing a fully solid component.
null
null
null
null
null
null
['Montalvo, J.I.', 'Hidalgo, M.A.']
2021-10-21T15:11:09Z
2021-10-21T15:11:09Z
2015
Mechanical Engineering
null
https://hdl.handle.net/2152/89390
eng
2015 International Solid Freeform Fabrication Symposium
Open
['3D printing', 'reinforced filament', 'natural fiber', 'reverse engineering']
3D Printing with Natural Fiber Reinforced Filament
Conference paper
https://repositories.lib.utexas.edu//bitstreams/997f7061-9325-40d0-a371-206958e86301/download
University of Texas at Austin
An initial study of 3d printing with compound filament using different plastic matrices and sugar cane bagasse as the filler was conducted. In order to do this, a reverse engineering process was made to several 3d printer extruders to determine how to change the extruder in order to be able to print with the filament. To obtain the filament, a plastic extruder was modified to obtain a compound filament of 1.75 mm using a 3x4 design of experiments with the factors percentage of fiber (10% 20% 30%) and type of matrix(PE,PP,ABS,PLA). The filaments obtained were tested to determine the mechanical properties and finally were used in a 3d printing to compare results.
null
null
null
null
null
null
['Song, Yong-Ak', 'Park, Sehyung', 'Hwang, Kyunghyun', 'Choi, Doosun', 'Jee, Haeseong']
2019-02-26T17:15:15Z
2019-02-26T17:15:15Z
1998
Mechanical Engineering
null
['https://hdl.handle.net/2152/73488', 'http://dx.doi.org/10.26153/tsw/638']
eng
1998 International Solid Freeform Fabrication Symposium
Open
['mechanical strength', 'rapid tooling techniques']
3D Welding and Milling for Direct Prototyping of Metallic Parts
Conference paper
https://repositories.lib.utexas.edu//bitstreams/2ff65214-fd4e-4373-9d70-8be62cbf4fc0/download
null
Welding has been used for the direct fabrication of metallic prototypes and prototype tools by several research institutes. Since welding alone is not able to deliver the accuracy and the surface quality needed for prototype tools, especially for injection molds, a combination with conventional machining is necessary. In this paper, welding and 5-axis milling are combined together for the direct fabrication of metallic parts. For welding, conventional CO2 arc welding is used. Test parts with conformal cooling channels an~ undercuts demonstrate the technological potential ofthis process combination for rapid tooling applications.
null
null
null
null
null
null
['Vaithilingam, J.', 'Saleh, E.', 'Tuck, C.', 'Wildman, R.', 'Ashcroft, I.', 'Hague, R.', 'Dickens, P.']
2021-10-21T19:54:35Z
2021-10-21T19:54:35Z
2015
Mechanical Engineering
null
https://hdl.handle.net/2152/89435
eng
2015 International Solid Freeform Fabrication Symposium
Open
['3D inkjet printing', 'drop-on-demand', 'conductive inks', 'conductive silver', 'PEDOT:PSS', 'flexible electronics', 'stretchable electronics']
3D-Inkjet Printing of Flexible and Stretchable Electronics
Conference paper
https://repositories.lib.utexas.edu//bitstreams/3a4d9a27-5c78-4a2f-83b9-27cbe16b12ab/download
University of Texas at Austin
Inkjet printing of conductive tracks on flexible and stretchable materials have gained considerable interest in recent years. Conductive inks including inks with silver nanoparticles, carbon based inks, inks containing poly (3,4-ethylenedioxythiophene) (PEDOT) doped with polystyrene sulfonic acid (PSS) are being researched widely to obtain a printed electronic patterns. In this study, we present drop-on-demand inkjet printing of conductive silver and PEDOT:PSS on a flexible and stretchable substrate. Process conditions for the inkjet printing of silver nano-particles and PEDOT:PSS were optimised and simple geometrical patterns (straight line and sinewave tracks) were printed. Surface profile, surface morphology and electrical resistance of the printed patterns were examined. The printed silver patterns were observed to be highly conductive; however when stretched, the patterns did not conduct due to the origination of cracks. The measured conductivity for the PEDOT:PSS patterns was significantly lower than the silver patterns; however, they remained conductive when stretched for up to 3 mm. When flexed, PEDOT:PSS remained conductive for a lower radius of curvature (10 mm) than the silver. Among the printed patterns, the sinewave pattern was observed to be superior for flexible electronics application.
null
null
null
null
null
null
['Wasserfall, Florens', 'Ahlers, Daniel', 'Hendrich, Norman', 'Zhang, Jianwei']
2021-10-28T22:19:47Z
2021-10-28T22:19:47Z
2016
Mechanical Engineering
null
https://hdl.handle.net/2152/89717
eng
2016 International Solid Freeform Fabrication Symposium
Open
['SMDs', 'SMD placement', 'SMD wiring', '3D-printable electronics', 'fused deposition modeling', '3D printing']
3D-Printable Electronics - Integration of SMD Placement and Wiring into the Slicing Process for FDM Fabrication
Conference paper
https://repositories.lib.utexas.edu//bitstreams/68a3b9d7-7cef-4c45-938b-94014b61a202/download
University of Texas at Austin
Several approaches to the integration of wires and electronic components into almost every existing additive fabrication process have been successfully demonstrated by a number of research groups in the last years. While the pure mechanical process of generating conductive wires inside of a printed object has proved to be feasible, the design, integration, routing and generation of toolpaths is still a laborious manual task. In this paper, we present a novel approach to place and wire SMDs in a three-dimensional object, based on schematics generated by conventional PCB design tools such as CadSoft EAGLE. Routing wires in an object for FDM manufacturing requires certain knowledge about the printer’s properties to meet the extruder characteristics, avoid non-fillable regions and electric shorts. Correspondingly for the slicing of conductive wires, the software must respect appropriate channel widths, avoid interrupted traces and ensure proper endpoints serving as contact pads for the SMDs. To fulfill those requirements, we implemented the design and routing software as a native extension of an existing slicing software. The user works in a three-dimensional representation of the final extruder toolpath, augmented by the routing information. The actual computing step is executed at the layer level by manipulating the polygons which represent the two-dimensional object topology and toolpath for each single layer, allowing the routing algorithm to avoid the generation of nonprintable traces. We successfully designed and printed some test objects including a force-sensor prototype, demonstrating a significant improvement in the usability and efficiency over manual solutions.
null
null
null
null
null
null
['Zhang, Feng', 'Zhang, Qiangqiang', 'Grove, Weston', 'Lin, Dong', 'Zhou, Chi']
2021-10-28T21:00:40Z
2021-10-28T21:00:40Z
2016
Mechanical Engineering
null
https://hdl.handle.net/2152/89699
eng
2016 International Solid Freeform Fabrication Symposium
Open
['micro-dispensing', 'directional freezing', '3D graphene oxide', '3D graphene aerogel', '3D printing']
3D-Printing Graphene Oxidize Based on Directional Freezing
Conference paper
https://repositories.lib.utexas.edu//bitstreams/0ab65d4b-9d07-46ab-97e8-66a36d8ecf32/download
University of Texas at Austin
This paper aims to provide a new process that is based on micro-dispensing and directional freezing to fabricate macro and micro controllable 3D graphene aerogel. In the first section, a design model of the proposed system to print 3D graphene oxide is presented, and the configurations are discussed in detail. The presented new method is contrasted to other few graphene 3D printing process. A process planning is provided includes the complete fabrication process and printing process. The physics mechanism behind the process is illustrated. A list of 2.5D and 3D printed samples are shown. Graphene Oxide solution is an easy to print material for micro-dispensing device, we successfully printed GO solutions in a stable and reliable way. Our freezing based 3D printing process matches well with freeze drying technology, which together composes the key step for fabricating truly 3D graphene aerogel.
null
null
null
null
null
null
['Wang, Qinguri', 'Tian, Xiaoyong', 'Huang, Lan']
2021-11-10T21:46:56Z
2021-11-10T21:46:56Z
2018
Mechanical Engineering
null
['https://hdl.handle.net/2152/90187', 'http://dx.doi.org/10.26153/tsw/17108']
eng
2018 International Solid Freeform Fabrication Symposium
Open
['4D printing', 'continuous fiber', 'composites', 'programmable morphing']
4D Printing Method Based on the Composites with Embedded Continuous Fibers
Conference paper
https://repositories.lib.utexas.edu//bitstreams/3b821575-aede-49c1-8309-fb09e19e90d9/download
University of Texas at Austin
Most of the current 4D printing technologies have the following defects: 1) the deformation shape is simple; 2) the deforming precision is poor; 3) the deformation process is always uncontinuous. In this study, a new 4D printing process based on the composites with embedded continuous fibers is proposed. In this process, a bilayer structure consisting of the top layer of continuous fibers and the bottom layer with resin is 3D printed. Due to the different thermal expansion coefficient and elastic modulus of the top and bottom layers, the structure will produce bending deformation when the temperature changes. It is found that the curvature value and the curvature direction of the composite structure can be precisely controlled by the angle of the intersecting fibers. The influence of fiber trajectory on curvature is studied, and then, the controllable deformation of any developable surface is achieved.
null
null
null
null
null
null
['Cai, Jiyu', 'Vanhorn, Austin', 'Mullikin, Casey', 'Stabach, Jennifer', 'Alderman, Zach', 'Zhou, Wenchao']
2021-10-21T20:20:05Z
2021-10-21T20:20:05Z
2015
Mechanical Engineering
null
https://hdl.handle.net/2152/89437
eng
2015 International Solid Freeform Fabrication Symposium
Open
['4D printing', 'soft robotics', 'robotic facial muscles']
4D Printing of Soft Robotic Facial Muscles
Conference paper
https://repositories.lib.utexas.edu//bitstreams/edf57068-d745-47f3-9fc1-929fa091461c/download
University of Texas at Austin
4D printing is an emerging technology that prints 3D structures with smart materials that can respond to external stimuli and change shape over time. 4D printing represents a major manufacturing paradigm shift from single-function static structures to dynamic structures with highly integrated functionalities. Direct printing of dynamic structures can provide great benefits (e.g., design freedom, reduced weight, volume, and cost) to a wide variety of applications, such as sensors and actuators, and robotics. Soft robotics is a new direction of robotics in which hard and rigid components are replaced by soft and flexible materials to mimic actuation mechanisms in life, which are crucial for dealing with uncertain and dynamic tasks or environments. However, little research on direct printing of soft robotics has been reported. This paper presents a study on 4D printing of soft robotic facial muscles. Due to the short history of 4D printing, only a few smart materials have been successfully 4D printed, such as shape memory and thermo-responsive polymers, which have relatively small strains (~8%). In order to produce the large motion needed for facial muscles, dielectric elastomer actuators (DEAs), operating like a capacitor with a sheet of elastomer sandwiched by two compliant electrodes and known as artificial muscle for its high elastic energy density and capability of producing large strains (~200%) compared to other smart materials, is chosen as the actuator for our robotic facial muscles. In this paper, we report the first fully 4D printed soft robotic face using DEAs. A literature review on DEAs is first presented. In order to select the right material for our soft robotic face, the performance of different silicone-based candidate materials is tested and compared. A soft robotic face is then designed and fabricated using the selected material to achieve facial emotions by the motion of its lip and pupils actuated by the DEAs. This study demonstrates a 4D printed soft robotic face for the first time and the potential of 4D printing of soft robotics.
null
null
null
null
null
null
['Kapil, Sajan', 'Negi, Seema', 'Joshi, Prathamesh', 'Sonwane, Jitendra', 'Sharma, Arun', 'Bhagchandani, Ranjeet', 'Karunakaran, K.P.']
2021-11-04T18:08:54Z
2021-11-04T18:08:54Z
2017
Mechanical Engineering
null
['https://hdl.handle.net/2152/89992', 'http://dx.doi.org/10.26153/16913']
eng
2017 International Solid Freeform Fabrication Symposium
Open
['hybrid layered manufacturing', 'rapid prototyping', '5-axis cladding', '5-axis slicing', 'non-planar slicing']
5-Axis Slicing Methods for Additive Manufacturing Process
Conference paper
https://repositories.lib.utexas.edu//bitstreams/0b4a3b44-b809-494a-a216-fd556fd90d0a/download
University of Texas at Austin
In metallic Additive Manufacturing (AM) processes such as Hybrid Layered Manufacturing (HLM), it is difficult to remove the support material used for realizing the overhanging/undercut features. Multi-axis kinematics can be used to eliminate the requirement of the support mechanism. In this work, two slicing methods have been proposed which utilize the benefits of multi-axis kinematics to eliminate the support mechanism. In the first method, planar slicing is used and the overhanging/undercut features are realized while keeping the growth of the component in the conventional Z-direction. In the second method, non-planar slicing is used, and the growth of the component need not necessarily be in the Z-direction; it can also be conformal to the selected feature of the component. Both these methods are explained through a case study of manufacturing an impeller by the HLM process.
null
null
null
null
null
null
['Chatham, Camden A.', 'Benza, Donald W.']
2024-03-25T21:58:45Z
2024-03-25T21:58:45Z
2023
Mechanical Engineering
null
['https://hdl.handle.net/2152/124309', 'https://doi.org/10.26153/tsw/50917']
en_US
2023 International Solid Freeform Fabrication Symposium
Open
['manufacturing', 'interface', 'engineering', 'polymer', '2023 Solid Freeform Fabrication Symposium']
A comparison of mechanical properties from natural and process-induced interfaces in filament extrusion AM of polymer blends
Conference paper
https://repositories.lib.utexas.edu//bitstreams/d7683458-5b04-482f-a8cc-dfbbbfcdd6c8/download
University of Texas at Austin
Polymer blends are commonly tuned for specific applications to achieve desired properties otherwise inaccessible or prohibitively expensive to obtain via homopolymers. The interfacial characteristics of the polymer A-polymer B interface and resultant domain sizes govern key performance properties. Micro- and meso-scale morphology forms through the interplay of surface forces between the polymers and between each polymer and the surrounding atmosphere. Analogously, the layer-layer and road-road interfaces of material extrusion (MEX) additive manufacturing (AM) govern key performance properties of printed parts. This work explores the effect of layer height on the thermomechanical performance of polystyrene (PS)-polycarbonate (PC) blends. Filament is prepared from a 50/50 weight ratio of the two polymers and compared against dual-nozzle printing where every layer alternates between PS or PC homopolymer forming a part with an overall 50/50 polymer ratio. Typical indicators of polymer blend compatibility are also studied.
null
null
null
null
null
null
['Ahmad, Nabeel', 'Bidar, Alireza', 'Ghiaasiaan, Reza', 'Gradl, Paul R.', 'Shao, Shuai', 'Shamsaei, Nima']
2024-03-25T22:54:42Z
2024-03-25T22:54:42Z
2023
Mechanical Engineering
null
['https://hdl.handle.net/2152/124329', 'https://doi.org/10.26153/tsw/50937']
en_US
2023 International Solid Freeform Fabrication Symposium
Open
['additive manufacturing', 'L-PBF', 'LP-DED', 'WAAM', 'Inconel 718']
A Comparison of Microstructure and Mechanical Performance of Inconel 718 Manufactured via L-PBF, LP-DED, and WAAM Technologies
Conference paper
https://repositories.lib.utexas.edu//bitstreams/dabc9dba-11ca-45d3-9c50-f5bcb709245a/download
University of Texas at Austin
The microstructure and mechanical properties of additively manufactured (AM) alloys can be significantly affected by variations in cooling rates, resulting from different process conditions across different additive manufacturing (AM) platforms. Therefore, it is crucial to understand the effect of manufacturing process on the microstructure and mechanical properties of AM Inconel 718. This study examines three AM processes: laser powder bed fusion, laser powder directed energy deposition, and wire arc additive manufacturing. Results show that fully heat treated laser powder bed fused (L-PBF) and wire arc additively manufactured (WAAM) Inconel 718 specimens exhibit higher strength compared to laser powder directed energy deposited (LP-DED) ones due to finer grain structure in L-PBF and retained dendritic microstructure in WAAM. The ductility in LP-DED Inconel 718 was slightly higher compared to WAAM and L-PBF due to relatively small carbide size, which causes stress concentration in a small material volume, leading to delayed fracture.
null
null
null
null
null
null
['Caballero, K.', 'Medrano, V.A.', 'Arrietam E.', 'Merino, J.', 'Ruvalcaba, B.', 'Ramirez, B.', 'Diemann, J.', 'Murr, L.E.', 'Wicker, R.B.', 'Godfrey, D.', 'Benedict, M.', 'Medina, F.']
2024-03-25T22:58:06Z
2024-03-25T22:58:06Z
2023
Mechanical Engineering
null
['https://hdl.handle.net/2152/124330', 'https://doi.org/10.26153/tsw/50938']
en_US
2023 International Solid Freeform Fabrication Symposium
Open
['AlSi7Mg alloy', 'laser powder bed fusion', 'EOS M290 system', 'SLM 280HL system', 'heat treatments', 'microindentation hardness', 'mechanical properties analysis']
A comparison of the mechanical behavior of AlSi7Mg alloy produced through additive manufacturing and subjected to different heat treatment and aging conditions
Conference paper
https://repositories.lib.utexas.edu//bitstreams/47020d4e-3f86-4e78-a12e-e716f20fd7a1/download
University of Texas at Austin
The versatility and adaptability of Aluminum F357 (AlSi7Mg) make it a popular material in the aerospace and defense industries. In this study, two different laser powder bed fusion systems, EOS M290, and SLM 280HL were used to create specimens of Aluminum F357. These specimens were subjected to five different heat treatments: As-built, stress relief (SR), hot isostatic pressing (HIP), T6, and HIP+T6) as per ASTM F3318-18 standard. The printed specimens were then reduced to tensile bars through machining and tested for mechanical properties as per ASTM E28 using an MTS Landmark tensile testing system. In addition to the mechanical behavior analysis, the study used a JEOL JSM-IT500 SEM to observe and document the fracture produced by the tensile test and a Qness 30 CHD Master+ microhardness testing system to obtain hardness (HV) values of the alloy. The results showed that specimens fabricated in the Z direction had a tendency for higher yield strengths of approximately 225 MPa and although these results were similar between LPBF systems some variances can still be seen. However, these differences between the LPBF systems were observed to be partially mitigated by heat treatments. In conclusion, this study highlights the significance of heat treatment on the mechanical properties of Aluminum F357. The results provide valuable information for the aerospace and defense industries to optimize their processes and produce high-quality components. The compatibility of LPBF system fabrication and the mitigation of differences observed between LPBF machines by heat treatments, further demonstrate the potential of this method for producing high-quality Aluminum F357 components.
null
null
null
null
null
null
['Liao, A.', 'Behera, D.', 'Cullinan, M.A.']
2024-03-25T22:59:58Z
2024-03-25T22:59:58Z
2023
Mechanical Engineering
null
['https://hdl.handle.net/2152/124332', 'https://doi.org/10.26153/tsw/50940']
en_US
2023 International Solid Freeform Fabrication Symposium
Open
['laser sintering', 'microscale', 'additive manufacturing']
A NOVEL COATING METHOD USED TO ENABLE MULTILAYER STRUCTURES WITH MICROSCALE SELECTIVE LASER SINTERING
Conference paper
https://repositories.lib.utexas.edu//bitstreams/d62c88c0-8d13-4085-a496-adb77aa3dd00/download
University of Texas at Austin
The microscale selective laser sintering process (µSLS) is an additive manufacturing technique that enables the creation of metal features with sub-5 µm in-plane resolution. In this process, a layer of metal nanoparticle ink is deposited onto a substrate and positioned beneath an optical subsystem with a nanopositioning stage. Using a digital micromirror device, a laser is spatially modulated to selectively heat up particles in desired regions to cause sintering. The substrate is then moved to a coating station where a new layer of nanoparticle ink is applied atop the sintered features. Initially, the slot-die coating process was adopted as the recoating method for this technique. However, due to challenges with depositing consistent ink thickness across the recoated part and limitations with the minimum layer thickness achievable, a new approach inspired by blade coating has been developed to achieve layer thicknesses of less than 1 µm.
null
null
null
null
null
null
['Barroi, A.', 'Schwarz, N.', 'Hermsdorf, J.', 'Bielefeld, T.', 'Kaierle, S.']
2024-03-26T22:59:55Z
2024-03-26T22:59:55Z
2023
Mechanical Engineering
null
['https://hdl.handle.net/2152/124438', 'https://doi.org/10.26153/tsw/51046']
en_US
2023 International Solid Freeform Fabrication Symposium
Open
['additive manufacturing', 'laser wire', 'titanium', 'gas chamber']
A small volume, local shielding gas chamber with low gas consumption for Laser Wire Additive Manufacturing of bigger titanium parts
Conference paper
https://repositories.lib.utexas.edu//bitstreams/16535e1d-86a5-4f46-a466-86d85ef8debc/download
University of Texas at Austin
This paper shows how additive manufacturing of large size titanium parts can be achieved by means of a mobile shielding gas chamber, without the consumption of excessive amounts of shielding gas. While welding, the oversized cover of the chamber can be slid to the sides without opening it. The laser head is only partly inserted into the chamber through the cover. This enables a small sized chamber and allows a quick filling with argon. Since the chamber has a low leakage, only small amounts of argon (5 l/min) are needed to maintain a sufficient welding atmosphere with less than 300 ppm oxygen. For large sized parts, the chamber can be repositioned on the substrate. It has flexible parts which can be fit to the already welded structures that otherwise would prevent the chamber from being put flat on the substrate. The limited build space inside the chamber requires a new welding strategy, which is suggested.
null
null
null
null
null
null
['Dwivedi, Rajeev', 'Dwivedi, Indira', 'Panwar, Arihant', 'Dwivedi, Bharat']
2024-03-26T20:32:23Z
2024-03-26T20:32:23Z
2023
Mechanical Engineering
null
['https://hdl.handle.net/2152/124398', 'https://doi.org/10.26153/tsw/51006']
en_US
2023 International Solid Freeform Fabrication Symposium
Open
['rocket', 'nozzle', 'additive manufacturing']
A Solid Free Form Fabrication Equipment to Manufacture Axisymmetric Parts with Improved Surface Quality
Conference paper
https://repositories.lib.utexas.edu//bitstreams/23219f6e-7166-4aea-b2c3-dab7969e68b5/download
University of Texas at Austin
Competitive and Hobby grade Rocket makers quite often build custom nozzles. Solid freeform fabrication is most natural choice for Manufacturing of the Nozzles. Different geometries can be quickly manufactured and tested. However, staircase effect and limited accuracy of 2-1/2 based deposition prevents the design intent from fabrication. Additionally, using different blends of ceramic and sustaining the geometry during curing becomes challenging. This research presents a unique 3D printing system that dispenses ceramic to enable manufacturing of axi-symmetric parts as continuous bead. Relative motion of the material dispenser and rotational substrate as well as unique path planning enables a continually sculpted surface to reduce the staircase effects.
null
null
null
null
null
null
['Ko, S.', 'Sagawa, T.', 'Yamagata, Y.', 'Aoki, S.', 'Abe, T.']
2024-03-26T23:02:23Z
2024-03-26T23:02:23Z
2023
Mechanical Engineering
null
['https://hdl.handle.net/2152/124439', 'https://doi.org/10.26153/tsw/51047']
en_US
2023 International Solid Freeform Fabrication Symposium
Open
['wire arc additive manufacturing', 'WAAM', 'test artifact', 'inspection process', 'sphere']
A SPHERICAL TEST ARTIFACT TO EVALUATE THREE-DIMENSIONAL FORM ACCURACY FOR WIRE ARC ADDITIVE MANUFACTURING
Conference paper
https://repositories.lib.utexas.edu//bitstreams/8ebe3882-a6e7-4a62-97e3-911878393aed/download
University of Texas at Austin
Additive manufacturing, including the wire arc additive manufacturing (WAAM), is gradually gaining attraction, and providing benefits in the aerospace and construction industries. In both industries, large-scale manufacturing capability and quality consistency of manufactured 3D parts are crucial. As part of quality evaluation, test artifacts for the geometric capability assessment are specified in ISO/ASTM52902-2019(E). On the other hand, the test artifact for curved wall is left undefined. This paper proposes a spherical shell shape as a representative of three-dimensional shapes that are supportless and feature large overhangs, for testing the geometric capability of a WAAM equipment. A mechanical configuration and deposition strategy are considered, which owns the potential to universally applying for depositing large-scale parts. A quality evaluation process for the sphere deposition was also described and experimentally demonstrated.
null
null
null
null
null
null
['Jalui, S.S.', 'Spurgeon, T.J.', 'Jacobs, E.R.', 'Chatterjee, A.', 'Stecko, T.', 'Manogharan, G.P.']
2021-12-07T18:48:33Z
2021-12-07T18:48:33Z
2021
Mechanical Engineering
null
['https://hdl.handle.net/2152/90755', 'http://dx.doi.org/10.26153/tsw/17674']
eng
2021 International Solid Freeform Fabrication Symposium
Open
['laser-powder bed fusion', 'additive manufacturing', 'surface roughness', 'abrasive flow machining', 'micro-CT scanning', 'hybrid AM']
Abrasive Flow Machining of Additively Manufactured Titanium: Thin Walls and Internal Channels
Conference paper
https://repositories.lib.utexas.edu//bitstreams/e59c70a1-7a26-4313-9c9f-1c783c890072/download
University of Texas at Austin
Metal additive manufacturing using Laser-Powder Bed Fusion (L-PBF) technique has enabled the metal manufacturing industry to use design tools with increased flexibility such as freeform internal channel geometries that benefit thermofluidic applications such as heat exchangers. A primary drawback of the L-PBF process is the as-built surface roughness, which is a critical factor in such surface-fluidic applications. In addition, complex internal channel geometries cannot be post-processed through traditional finishing and polishing methods, and require advanced finishing processes such as Abrasive Flow Machining (AFM). In this original study, the effects of AM design including geometrical changes at the inlets, internal channel and wall thickness of thin features are experimentally studied on Ti64 L-PBF parts. A novel surface roughness inspection technique using micro-CT data is also presented. The internal channels with larger dimensions underwent 40% improvement in surface roughness with no statistically significant change in diameter whereas the channels with smaller dimensions and bends had a 38% improvement in surface roughness accompanied by a 6% increase in diameter. While there was as much as 30% improvement in surface roughness values, the thin walls less than 0.4 mm in dimension were deformed under the AFM pressure after just 5 cycles.
null
null
null
null
null
null
['Karunakaran, Rakeshkumar', 'Ortgies, Sam', 'Green, Ryan', 'Barelman, William', 'Kobler, Ian', 'Sealy, Michael']
2021-12-01T21:19:08Z
2021-12-01T21:19:08Z
2021
Mechanical Engineering
null
['https://hdl.handle.net/2152/90616', 'http://dx.doi.org/10.26153/tsw/17535']
eng
2021 International Solid Freeform Fabrication Symposium
Open
['magnesium', 'corrosion', 'powder bed fusion', 'fracking']
Accelerated Corrosion Behavior of Additive Manufactured WE43 Magnesium Alloy
Conference paper
https://repositories.lib.utexas.edu//bitstreams/df537715-f19f-405b-84aa-0b393b278dc0/download
University of Texas at Austin
Magnesium alloys are capable of withstanding the high temperatures and pressures needed in oil and gas fracking operations followed by rapid and complete dissolution in days. Dissolvable magnesium plugs are used in fracking to enable longer lateral wellbores by eliminating mill-outs and the associated debris clogging. To increase extraction efficiency, the key technical challenge is determining how to increase the strength of a high corrosion rate magnesium device that enables higher pressures while maintaining high corrosion rates. Topologically modified dissolvable plugs fabricated by additive manufacturing is proposed as a solution to fabricate high strength and high corrosion rate fracture plugs. Corrosion of magnesium is dependent on surface area exposed to corrosive media and is easily manipulated by additive manufacturing. This study highlights the development of optimal powder bed fusion process parameters for WE43 magnesium alloy and investigates the corrosion behavior of printed WE43 in a salt solution concentrated with sodium bicarbonate to initiate highly accelerated corrosion. Printed WE43 corroded three times faster than an as-rolled sample and was driven by the mechanical and materials properties formed by printing.
null
null
null
null
null
null
['Pintat, T.', 'Greul, M.', 'Greulich, M.']
2018-10-04T19:57:36Z
2018-10-04T19:57:36Z
1995
Mechanical Engineering
doi:10.15781/T21C1V11T
http://hdl.handle.net/2152/68708
eng
1995 International Solid Freeform Fabrication Symposium
Open
['SEM', 'postprocessing', 'electrodeposition']
Accuracy and Mechanical Behavior of Metal Parts Produced by Lasesrintering
Conference paper
https://repositories.lib.utexas.edu//bitstreams/8417d67b-d4f4-4b3f-bdb6-18a97082d69b/download
null
The work shows the mechanical properties of direct laser-sintered metal parts. The parts were tested after sintering and after an infiltration. Furthermore the accuracy of the parts was measured. Micrographs of the parts show the microstructure of the copper-nicker-tin alloy. The achievable complexity of parts is demonstrated by examples. An overview of future activities is given.
null
null
null
null
null
null
['Eosoly, S.', 'Ryder, G.', 'Tansey, T.', 'Looney, L.']
2020-03-10T16:09:47Z
2020-03-10T16:09:47Z
2007
Mechanical Engineering
null
['https://hdl.handle.net/2152/80221', 'http://dx.doi.org/10.26153/tsw/7240']
eng
2007 International Solid Freeform Fabrication Symposium
Open
selective laser sintering
Accuracy and Mechanical Properties of Open-Cell Microstructures Fabricated by Selective Laser Sintering
Conference paper
https://repositories.lib.utexas.edu//bitstreams/6815d665-f567-474c-8c55-54aba7a0b24e/download
null
This paper investigates the applicability of selective laser sintering (SLS) for the manufacture of scaffold geometries for bone tissue engineering applications. Porous scaffold geometries with open-cell structure and relative density of 10-60 v% were computationally designed and fabricated by selective laser sintering using polyamide powder. Strut and pore sizes ranging from 0.4 - 1 mm and 1.2 -2 mm are explored. The effect of process parameters on compressive properties and accuracy of scaffolds was examined and outline laser power and scan spacing were identified as significant factors. In general, the designed scaffold geometry was not accurately fabricated on the micron-scale. The smallest successfully fabricated strut and pore size was 0.4 mm and 1.2 mm, respectively. It was found that selective laser sintering has the potential to fabricate hard tissue engineering scaffolds. However the technology is not able to replicate exact geometries on the micron-scale but by accounting for errors resulting from the diameter of the laser and from the manufacturing induced geometrical deformations in different building directions, the exact dimensions of the manufactured scaffolds can be predicted and controlled indirectly, which corresponds favorably with its application in computer aided tissue engineering.
null
null
null
null
null
null
['Volpato, Neri', 'Childs, Thomas H.C.', 'Pennington, Alan de']
2019-09-23T16:14:16Z
2019-09-23T16:14:16Z
2000
Mechanical Engineering
null
['https://hdl.handle.net/2152/75953', 'http://dx.doi.org/10.26153/tsw/3052']
eng
2000 International Solid Freeform Fabrication Symposium
Open
Shelling
Accuracy Effects of Shelling a Part in the SLS Process 306
Conference paper
https://repositories.lib.utexas.edu//bitstreams/ba27c435-11ae-4723-b417-55134991338d/download
null
In order to reduce SLS process time in the manufacture of a mould insert, the idea of shelling the geometry of the insert has been tested. Some shelling strategies have been successful with the RapidToolTM process, proving the feasibility of the idea. It has been observed in the tests, for both polymer and RapidSteel2.0TM materials, that size accuracy, particularly of small features in the scanning (X) direction, depends on vector length (VL). When a sudden change in VL occurs, this leads to steps on the sintered surface. This paper presents both experimental observations of this and simulation results from a finite element model.
null
null
null
null
null
null
['Gregorian, A.', 'Elliott, B.', 'Navarro, R.', 'Ochoa, F.', 'Singh, H.', 'Monge, E.', 'Foyos, J.', 'Noorani, R.', 'Fritz, B.', 'Jayanthi, S.']
2019-10-09T16:13:53Z
2019-10-09T16:13:53Z
2001
Mechanical Engineering
null
['https://hdl.handle.net/2152/76150', 'http://dx.doi.org/10.26153/tsw/3239']
eng
2001 International Solid Freeform Fabrication Symposium
Open
Prototyping
Accuracy Improvement in Rapid Prototyping Machine (FDM-1650)
Conference paper
https://repositories.lib.utexas.edu//bitstreams/2a18cbee-5035-40e8-856f-efb7fa2a26d7/download
null
Over the past few years, improvements in equipment, materials, and processes have enabled significant improvements in the accuracy of Fused Deposition Modeling (FDM) technology. This project will investigate the present in-plane accuracy of a particular FDM machine using the benchmark “User Part” developed by the North American StereoLithography User Group (NASUG) and show the effect of optimal Shrinkage Compensation Factors (SCF) on the accuracy of the prototyped parts. The benchmark parts were built on the FDM-1650 prototyping machine and a total of 46 measurements were taken in the X and Y planes using a Brown & Sharpe Coordinate Measuring Machine (CMM). The data was then analyzed for accuracy using standard formulas and statistics, such as mean error, standard deviation, residual error, rms error, etc. The optimal SCF for the FDM-1650 machine was found to be 1.007 or 0.7%.
This work was funded by a National Science Foundation (NSF) grant to Loyola Marymount University for their Research Experience for Undergraduates program.
null
null
null
null
null
['Pang, Thomas H.', 'Guertin, Michelle D.', 'Nguyen, Hop D.']
2018-10-10T15:33:37Z
2018-10-10T15:33:37Z
1995
Mechanical Engineering
doi:10.15781/T2X92238B
http://hdl.handle.net/2152/68755
eng
1995 International Solid Freeform Fabrication Symposium
Open
['Rapid prototyping', 'SLA', 'stereolithography']
Accuracy of Stereolithography Parts: Mechanism and Modes of Distortion for a "Letter-H" Diagnostic Part
Conference paper
https://repositories.lib.utexas.edu//bitstreams/fa40a594-bdda-44c1-9ce7-6b68228e4b42/download
null
Rapid Prototyping and Manufacturing (RP&M) users need to compare the accuracy of various commercially available RP&M materials and processes. A good diagnostic test for both material and the fabrication process involves a 4-inch long "letter-H" diagnostic part. This diagnostic part, known as "H-4", was developed to measure the inherent dimensional characteristics ofvarious RP&M build materials. It is also less dependent on the calibration status of particular RP&M machines, and is excellent for the purpose of generating simple but meaningful accuracy information, which can be used to further understand the mechanism and the modes of distortion in RP&M materials. H-4 parts were prepared and built in Stereolithography Apparatus (SLA) using Ciba-Geigy epoxy based resins SL 5170 and SL 5180, and results were compared to acrylate based SL 5149. Experimental data involving the magnitude, mechanism, and the modes of distortion for these three resins are analyzed in this paper.
null
null
null
null
null
null
['Crockett, R. S.', 'Horvath, T.', 'Koch, M.', 'Yang, M.']
2020-02-17T15:43:02Z
2020-02-17T15:43:02Z
2004
Mechanical Engineering
null
['https://hdl.handle.net/2152/80014', 'http://dx.doi.org/10.26153/tsw/7039']
eng
2004 International Solid Freeform Fabrication Symposium
Open
Solid Freeform Fabrication
Accurate Heart Model for Pacemaker Development in SFF
Conference paper
https://repositories.lib.utexas.edu//bitstreams/7ecc8ca7-c7ee-4ef8-b2df-61b62028610d/download
null
Medical imaging combined with SFF techniques were used to create detailed CAD and physical heart models for commercial development of Pacemakers. Using a data set of 2D optical slice images of the human heart at 1mm spacing obtained from the Visible Human Project, a 3D CAD model was constructed by masking the features of interest in each slice. Normals on the resulting .stl file were inverted to create a single-piece mold, which was built in starch using 3D Printing. Flexible silicone was cast into this mold, and the starch was dissolved away to produce the final physical heart model. The resulting model simulates the mechanical properties of an actual heart, with medically accurate internal and external details including major veins & arteries, coronary sinus, etc.
null
null
null
null
null
null
Levi, Heim
2018-04-16T17:40:17Z
2018-04-16T17:40:17Z
1991
Mechanical Engineering
doi:10.15781/T2513VC7R
http://hdl.handle.net/2152/64312
eng
1991 International Solid Freeform Fabrication Symposium
Open
['rapid prototyping', 'Solid Ground Curing Technology', 'stereolithography']
Accurate Rapid Prototyping
Conference paper
https://repositories.lib.utexas.edu//bitstreams/b2e4f5af-9514-4e14-b1aa-d8ab1316fe14/download
null
The first stage of Rapid Prototyping life cycle as a new technology in the marketplace is gradually ending, and the second stage has already started. Many new vendors have introduced their products in this field, utilized different, new technologies or improvements of the existing ones. The first introduction of the RP concept and Stereolithography created a stunning impression in the marketplace. After a couple of years, as customers and users have gained much experience and understanding or RP technology, the first enthusiasm started making way to more serious and demanding approach. This is very well reflected in the thorough evaluations of the different technologies available today in the marketplace, done by customers looking for a technology that will best fit their needs. This is actually why most of us are here today.
null
null
null
null
null
null
['Loney, D.A.', 'Zhou, W.', 'Rosen, D.W.', 'Degertekin, F.L.', 'Fedorov, A.G.']
2021-09-30T13:33:59Z
2021-09-30T13:33:59Z
2010
Mechanical Engineering
null
['https://hdl.handle.net/2152/88240', 'http://dx.doi.org/10.26153/tsw/15181']
eng
2010 International Solid Freeform Fabrication Symposium
Open
['acoustics', 'Additive Manufacturing via Microarray Deposition', 'ultrasonic atomizer', 'high viscosity fluid injection', '3D inkjet manufacturing']
Acoustic Analysis of Viscous Fluid Ejection Using Ultrasonic Atomizer
Conference paper
https://repositories.lib.utexas.edu//bitstreams/3b9a63a6-f12b-4c12-bda1-4baac0a43cca/download
University of Texas at Austin
The acoustics of the Additive Manufacturing via Microarray Deposition (AMMD) system based on a ultrasonic atomizer is investigated for printing high viscosity fluids for 3D inkjet manufacturing applications. The ultrasonic atomizer incorporates a piezoelectric transducer, a material reservoir, and a silicon micromachined array of acoustic horn structures as ejection nozzles. When driven at the resonance frequencies of the fluid cavity, the nozzle geometry focuses the acoustic waves resulting in a locally increased pressure gradient at the nozzle apex. Previously, AMMD has demonstrated successful ejection of fluids with viscosity as high as 3000 mN-s/m2, overcoming the viscosity limitations traditionally associated with piezoelectric droplet formation. However, the physics of ejection of such high-viscosity fluids is not well understood. This work focuses on understanding the acoustics of the AMMD system through complimentary simulations and experimental characterization. Specifically, ANSYS finite element software was used to model acoustic wave attenuation due to viscosity inside the material cavity and its implication on the pressure gradient at nozzle apex, which drives the fluid ejection. Additionally, the affect of fluid attenuation on cavity resonance modes, both the frequency and the quality factor, is characterized for fluids of a large variation range in viscosity. Finally, preliminary guidelines for improved design and efficient operation of the AMMD system are formulated based on an insight into a device’s acoustic behavior with high viscosity fluids.
null
null
null
null
null
null
['Kouprianoff, D.', 'Luwes, N.', 'Yadroitsava, I.', 'Yadroitsev, I.']
2021-11-15T21:53:40Z
2021-11-15T21:53:40Z
2018
Mechanical Engineering
null
['https://hdl.handle.net/2152/90283', 'http://dx.doi.org/10.26153/tsw/17204']
eng
2018 International Solid Freeform Fabrication Symposium
Open
['online monitoring', 'online detection', 'acoustic emission', 'fusion defect', 'balling effect', 'single tracks', 'metal laser powder bed fusion']
Acoustic Emission Technique for Online Detection of Fusion Defects for Single Tracks During Metal Laser Powder Bed Fusion
Conference paper
https://repositories.lib.utexas.edu//bitstreams/34ddc76c-8dca-4f50-940a-5a7e46a3e6c1/download
University of Texas at Austin
One of the main drawbacks of laser based powder bed fusion, is lack of fusion between tracks due to non-optimal input process parameters, scanning and building strategies and/or inhomogeneity in the delivered powder layer. Unstable geometrical characteristics of single tracks and high roughness of the powder layer can cause porosity in 3 dimensional printed parts. In this study a non-destructive online monitoring technique, using acoustic emission was utilized to determine lack of fusion and balling effect of single tracks. This phenomenon was simulated by using an increased powder layer thickness. Short Time Fourier Transform was used as a tool for analysis of the acoustic behaviour of the system and it was compared with the acoustic emission (AE) recorded during processing of single tracks.
null
null
null
null
null
null
['Khurana, Jivtesh B.', 'Dinda, Shantanab', 'Simpson, Timothy W.']
2021-11-04T14:39:17Z
2021-11-04T14:39:17Z
2017
Mechanical Engineering
null
https://hdl.handle.net/2152/89971
eng
2017 International Solid Freeform Fabrication Symposium
Open
['active z printing', 'part strength', '3D printing', 'fused filament fabrication', 'design of experiments']
Active - Z Printing: A New Approach to Increasing 3D Printed Part Strength
Conference paper
https://repositories.lib.utexas.edu//bitstreams/a7ebc85b-565f-4137-9864-baca0e739b29/download
University of Texas at Austin
Research suggests that topology and build parameters in Fused Filament Fabrication (FFF) play a vital role in determining mechanical properties of parts produced by this technique. In particular, the use of 2D layers printed parallel to the build surface produces high anisotropy in parts making them the weakest when loaded perpendicular to the layer interfaces. We investigate a novel approach that uses non-planar 3D layer shapes - Active Z printing, to improve mechanical strength through alignment of localized stress tensors parallel to the deposition paths. Sinusoidal layer shapes are used with varying amplitude, frequency, and orientation. Design of experiments is performed to correlate effect of varying shape and orientation of sinusoidal layer shapes on flexural strength of parts. Based on this, the results are used to decide parameters to be studied further and characterize their effect on the strength of parts.
null
null
null
null
null
null
['Saari, M.', 'Galla, M.', 'Cox, B.', 'Richer, E.', 'Krueger, P.', 'Cohen, A.']
2021-10-19T17:40:27Z
2021-10-19T17:40:27Z
2015
Mechanical Engineering
null
https://hdl.handle.net/2152/89306
eng
2014 International Solid Freeform Fabrication Symposium
Open
['Fiber Encapsulation Additive Manufacturing', 'electromechanical devices', 'active devices', 'device fabrication']
Active Device Fabrication Using Fiber Encapsulation Additive Manufacturing
Conference paper
https://repositories.lib.utexas.edu//bitstreams/06b4b2b7-fdce-4e28-b6d3-4280f5b6ec34/download
University of Texas at Austin
Fiber Encapsulation Additive Manufacturing (FEAM) is a novel solid freeform fabrication process in which a fiber and a matrix are co-deposited simultaneously within a single printer along straight and curved 2-D and 3-D paths. Using a FEAM approach in which the fiber is a metal wire and the matrix is a thermoplastic polymer, simple electromechanical devices such as voice coils, inductive sensors, and membrane switches have been successfully produced. This paper will present an overview of the FEAM process, describe several fabricated devices, and discuss recent developments in controllably stopping and starting the wire, and in creating electrical junctions between individual wires, which together enable much more complex devices to be made.
null
null
null
null
null
null
['Adams, Gavin', 'Meisel, Nicholas']
2024-03-26T16:53:19Z
2024-03-26T16:53:19Z
2023
Mechanical Engineering
null
['https://hdl.handle.net/2152/124371', 'https://doi.org/10.26153/tsw/50979']
en_US
2023 International Solid Freeform Fabrication Symposium
Open
['continuous carbon fiber', '3D printing', 'DfAM', 'additive manufacturing']
ADAPTING A DESIGN FOR ADDITIVE MANUFACTURING WORKFLOW TO ACCOUNT FOR CONTINUOUS CARBON FIBER REINFORCED PARTS
Conference paper
https://repositories.lib.utexas.edu//bitstreams/dbfa8d81-6e41-46ce-a646-31e62981f667/download
University of Texas at Austin
The use of continuous carbon fiber (CCF) reinforcement in material extrusion 3D printing has the potential to revolutionize the material extrusion field of additive manufacturing. Notably, the Markforged X7 system utilizes this CCF reinforcement with the aim to produce parts with mechanical results rivaling or surpassing those of aluminum. However, due to certain constraints with the deposition of CCF in material extrusion parts, such as an inability for CCF to be deposited throughout layers in the Z-direction, traditional design for additive manufacturing (DfAM) techniques need to be reevaluated. This paper will explore (1) how existing DfAM considerations (e.g., topology optimization, functional integration, minimum feature size, etc.) can be tailored to CCF and (2) how an existing DfAM workflow can be adapted to account for manufacturing limitations specific to the deposition of CCF. The research is demonstrated through a hoist sling case study, which highlights the importance of considering fiber orientation and routing in the design stage to ensure accurate CCF reinforcement and achieve ideal mechanical results relative to the loads associated with the part. The result is an initial, potentially valuable workflow for designing CCF parts to be created using AM.
null
null
null
null
null
null
Boudreaux, J.C.
2018-11-16T14:47:59Z
2018-11-16T14:47:59Z
1996
Mechanical Engineering
doi:10.15781/T2V40KJ88
http://hdl.handle.net/2152/70282
eng
1996 International Solid Freeform Fabrication Symposium
Open
['SLA', 'SFF', 'SLS']
An Adaptive Control Architecture for Freeform Fabrication
Conference paper
https://repositories.lib.utexas.edu//bitstreams/cbf0c01a-b372-4c8b-8650-15fe3aea5261/download
null
null
null
null
null
null
null
null
['Vouzelaud, F.A.', 'Bagchi, A.']
2018-04-19T18:36:20Z
2018-04-19T18:36:20Z
1992
Mechanical Engineering
doi:10.15781/T2QB9VP36
http://hdl.handle.net/2152/64411
eng
1992 International Solid Freeform Fabrication Symposium
Open
['Department of Mechanical Engineering', 'FFF', 'free form frabrication']
Adaptive Laminated Machining for Prototyping of Dies and Molds
Conference paper
https://repositories.lib.utexas.edu//bitstreams/21a83f11-db41-490f-8a01-3a16686bdbdf/download
null
Adaptive laminated machining is the fusion of slicing a solid model into layers and producing parts by CNC milling machines. Unlike other solid freeform fabrication processes which create the part by addition of material, adaptive laminated machining can create solid parts by selectively removing in layers. The research issues and practical limitations on shape and manufacturability are thus different from other processes. However, the biggest advantage is the ability to obtain a solid metal part such as a die or a mold directly. In this paper, the concept of this technique, and initial results and parts produced in Clemson will be presented. In addition, future research needs and issues will be discussed.
null
null
null
null
null
null
Chalavadi, Pradeep
2024-03-27T03:35:56Z
2024-03-27T03:35:56Z
2023
Mechanical Engineering
null
['https://hdl.handle.net/2152/124469', 'https://doi.org/10.26153/tsw/51077']
en_US
2023 International Solid Freeform Fabrication Symposium
Open
['adaptive meshing', 'octree data structure', 'voxel-based mesh', 'additive manufacturing']
ADAPTIVE MESHING FRAMEWORK USING OCTREE DATA STRUCTURE FOR VOXEL BASED MESHES
Conference paper
https://repositories.lib.utexas.edu//bitstreams/a6afdf34-6629-47bf-a9d5-e68bc46a1f6b/download
University of Texas at Austin
We present an adaptive meshing framework for voxel-based meshes, designed for use in various process simulations for additive manufacturing, such as thermal, distortion, grain growth, etc. The framework uses an octree data structure to represent the meshes, and a coarsening/refinement algorithm to generate coarser and finer meshes. The algorithm preserves a 2:1 ratio of coarse to fine meshes to maintain desired accuracy. Efficient tree traversal is used for fast nodal/Gaussian solution mapping. In many cases, selective element coarsening enables the reduction of the number of nodes to be solved by the iterative matrix solver. To maintain accuracy at boundary, the algorithm can be configured to maintain a certain level of fine mesh at boundary. When part and support mesh touch, they are automatically flagged to be not combined to be coarsened at any stage. Overall, the algorithm enables reduction of solution nodes while maintaining desired accuracy at areas of interest.
null
null
null
null
null
null
['Xiangping, Wang', 'Haiou, Zhang', 'Guilan, Wang', 'Lingpeng, Wu']
2021-10-18T22:38:58Z
2021-10-18T22:38:58Z
2014
Mechanical Engineering
null
https://hdl.handle.net/2152/89275
eng
2014 International Solid Freeform Fabrication Symposium
Open
['Hybrid Plasma Deposition and Milling', 'adaptive slicing', 'multi-axis layered manufacturing']
Adaptive Slicing for Multi-Axis Hybrid Plasma Deposition and Milling
Conference paper
https://repositories.lib.utexas.edu//bitstreams/8ae1bbb8-3c7f-4d0a-8ccf-54169ea147d8/download
University of Texas at Austin
Hybrid Plasma Deposition and Milling (HPDM), a five-axis manufacturing system integrated material additive and subtractive processes, can be used to create overhang metallic components directly without the usage of sacrificial support structure. Different from conventional slicing methods, a new slicing algorithm with changeable direction and thickness is proposed in this paper. Minimal overhang length is selected as the objective function to optimize the build direction. The thickness is adjusted to meet allowable overhang length and allowable cups height. The input mesh is first decomposed into non-uniform thickness segment meshes and then each segment is cut into uniform thickness slices. The output slices consist of split slices between two adjacent segment meshes and inner slices for each segment mesh. Examples and analyses confirm the feasibility and effectiveness.
null
null
null
null
null
null
['Suh, Young Seok', 'Wozny, Michael J.']
2018-10-03T18:40:57Z
2018-10-03T18:40:57Z
1994
Mechanical Engineering
doi:10.15781/T21J97T0Z
http://hdl.handle.net/2152/68677
eng
1994 International Solid Freeform Fabrication Symposium
Open
['SFF', '3D aliasing', 'CAD']
Adaptive Slicing of Solid Freeform Fabrication Processes
Conference paper
https://repositories.lib.utexas.edu//bitstreams/b6f350a7-565a-4911-baf9-5ff682c022be/download
null
The Solid Freeform Fabrication (SFF) process significantly reduces part specific setup manufacturing lead time. This process has been primarily used in fabricating prototypes for design visualization and verification. However, the major impact of this process on the future of manufacturing technology would be the possibility offabricating functional parts for end use. One ofthe obstacles to this goal is the insufficient accuracy ofthe final physical part produced by the process. From the software point of view, the major sources of the inaccuracy come from the inappropriate data transfer format and the 3D aliasing' or Stair-stepping' problem. The '3D aliasing' problem can be reduced by adapting the layer thickness to the geometry of the part. In this paper, the procedure of adaptive slicing from the exact representation ofthe part model is described. This will improve part accuracy and minimize building time especially for the parts with highly curved surfaces. The procedures are implemented and a comparison to the conventional uniform layer thickness method will be discussed.
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null
['Unnanon, Kittnan', 'Cormier, Denis', 'Sanii, Ezat']
2019-09-23T15:58:28Z
2019-09-23T15:58:28Z
2000
Mechanical Engineering
null
['https://hdl.handle.net/2152/75947', 'http://dx.doi.org/10.26153/tsw/3046']
eng
2000 International Solid Freeform Fabrication Symposium
Open
Inkjet
Adaptive Slicing With the Sanders Prototype Inkjet Modeling System 259
Conference paper
https://repositories.lib.utexas.edu//bitstreams/fb087c21-10e9-41e5-aaff-a468ef14be59/download
null
This paper presents one of the first known in depth studies of the Sanders Prototype inkjet modeling process. A process capability study was performed in order to determine the relationship between process parameter levels and the resulting surface roughness. The data was used to create a predictive model of surface roughness using a backpropagation neural network. Test results indicate that the network is quite effective at generalizing to new process configurations. The predictive surface roughness model is used in a newly developed inkjet modeling adaptive slicing algorithm. On a region-by-region basis, the algorithm determines the fastest machine configuration that can be used to build a part while satisfying the surface roughness requirements. The adaptive slicing system has been tested, and results documenting substantial time and cost savings are presented.
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null
['Coulson, Kevin', 'Toombs, Joseph', 'Gu, Magnus', 'Taylor, Hayden']
2021-12-06T23:50:41Z
2021-12-06T23:50:41Z
2021
Mechanical Engineering
null
['https://hdl.handle.net/2152/90723', 'http://dx.doi.org/10.26153/tsw/17642']
eng
2021 International Solid Freeform Fabrication Symposium
Open
['adaptive voxelization', 'computed axial lithography', 'printing generation', 'compensational time']
Adaptive Voxelization for Rapid Projection Generation in Computed Axial Lithography
Conference paper
https://repositories.lib.utexas.edu//bitstreams/7ee4836f-55c2-4eda-8376-d6b0ccb7483e/download
University of Texas at Austin
Computed axial lithography (CAL) is a tomographic additive manufacturing technology that offers exceptionally fast printing in a wide range of materials. CAL involves pre-computing a sequence of light patterns to be projected into a photopolymer. For a uniform spatial discretization of the target geometry, computational time scales inversely with the cube of the discretization pitch, which makes it challenging to exploit the full space-bandwidth product of available spatial light modulators. This work introduces an adaptive voxelization approach to reduce computational expense. Using one of several proposed mesh-based complexity analyses, a CAD model is recursively subdivided into stacked sub-meshes of varying voxel resolution. These complexity methods can be tailored to emphasize complexity in particular regions. Each sub-mesh is then independently voxelized before projections are generated and optimized in parallel. On a four-core CPU, this method results in a 2 − 6 × speedup with applications in high-precision CAL and other voxel-based additive manufacturing computations.
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null
['Shusteff, Maxim', 'Panas, Robert M.', 'Henriksson, Johannes', 'Kelly, Brett E.', 'Browar, Allison E.M.']
2021-10-28T15:39:37Z
2021-10-28T15:39:37Z
2016
Mechanical Engineering
null
https://hdl.handle.net/2152/89665
eng
2016 International Solid Freeform Fabrication Symposium
Open
['holographic lithography', 'additive manufacturing', '3D structures']
Additive Fabrication of 3D Structures by Holographic Lithography
Conference paper
https://repositories.lib.utexas.edu//bitstreams/9bceeb91-6f5c-4e8f-b172-7015d7b86823/download
University of Texas at Austin
As additive manufacturing (AM) technologies advance and mature, the geometric constraints imposed by fabricating 2D planar layers become increasingly important to overcome. In the realm of light-driven AM fabrication, holography provides a promising avenue toward true 3D structures. Being capable of recording and reconstructing 3D information, holographic shaping of the light field can enable direct 3D fabrication in photopolymer resins. We have conceptualized, designed, and built a prototype holographic additive micromanufacturing system, incorporating a liquid-crystal-on-silicon (LCoS) spatial light modulator (SLM) to redirect light energy at the build volume by spatial control of the phase distribution. Here we report the system design, design parameter trade-offs relevant for producing 3D structures, and initial fabrication results.
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null
['Ramesh, S.', 'Eldakroury, M.', 'Rivero, I.V.', 'Frank, M.C.']
2021-11-04T20:59:48Z
2021-11-04T20:59:48Z
2017
Mechanical Engineering
null
['https://hdl.handle.net/2152/90027', 'http://dx.doi.org/10.26153/16948']
eng
2017 International Solid Freeform Fabrication Symposium
Open
['bioplotting', 'chitosan', 'cryomilling', 'additive fabrication', 'bone tissue engineering']
Additive Fabrication of Polymer-Ceramic Composite for Bone Tissue Engineering
Conference paper
https://repositories.lib.utexas.edu//bitstreams/6823bbbd-6dba-4100-8ea5-d11353d371a0/download
University of Texas at Austin
The objective of this study is to manufacture chitosan-based biocomposite 3-D scaffolds through additive fabrication for promoting the regeneration of bone defects. Additive manufacturing has enabled the production of effective scaffolds by overcoming traditional limitations such as suboptimal distribution of cells, and poor control over scaffold architecture. In this study, cryomilled biocomposites comprising of poly (lactic) acid (PLA), chitosan (CS) and tricalcium phosphate (TCP) provided the basis for the generation of hydrogels, which were then utilized for the fabrication of scaffolds with orthogonal (0, 90) geometry. Rheological studies were conducted using a rotational rheometer to identify the ideal hydrogel concentration for the continuous production of scaffolds. The scaffolds were fabricated using a 3-axis computerized numerical control (CNC) which was modified to function as a customized bioplotter. Scanning electron microscopy (SEM) was used to observe the morphology of the bioplotted scaffolds. Finally, a short-term stability (14 days) study was conducted to analyze the in vitro degradation behavior of the scaffolds in phosphate buffer saline (PBS).
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['Bandari, Yashwanth K.', 'Williams, Stewart W.', 'Ding, Jialuo', 'Martina, Filomeno']
2021-10-19T15:47:24Z
2021-10-19T15:47:24Z
2015
Mechanical Engineering
null
https://hdl.handle.net/2152/89305
eng
2014 International Solid Freeform Fabrication Symposium
Open
['additive manufacture', 'direct feed', 'robotics', 'cost']
Additive Manufacture of Large Structures: Robotic or CNC Systems?
Conference paper
https://repositories.lib.utexas.edu//bitstreams/6cb88baa-342a-447d-b878-8f44a89f9440/download
University of Texas at Austin
Additive manufacture of metre scale parts requires direct feed processes such as blown powder or wire feed combined with lasers or arcs. The overall system can be configured using either a robotic or Computer Numerical Controlled (CNC) gantry system. There are many factors that determine which of these is best and this will be presented in this paper. Some factors are inherent to the specific process type such as accuracy/resolution and any requirement for reorientation of the feedstock and heat source. Other factors depend on the particular application including material type, shielding options, part size/complexity, required build strategies and management of distortion. Further considerations include the incorporation of ancillary processes such as cold work, machining or inspection. The relative influence of these factors will be discussed. Cost implications for the different approaches will be highlighted based upon the type of process being utilized. Examples are provided where both robotic and CNC options have been evaluated and the best solution found.
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['Aydin, I.', 'Akarcay, E.', 'Gumus, O.F.', 'Yelek, H.', 'Engin, C.B.']
2021-11-30T22:13:34Z
2021-11-30T22:13:34Z
2019
Mechanical Engineering
null
['https://hdl.handle.net/2152/90567', 'http://dx.doi.org/10.26153/tsw/17486']
eng
2019 International Solid Freeform Fabrication Symposium
Open
['additive manufacturing', 'finite element analysis', 'lattice structures', 'maraging steel', 'mechanical properties', 'vehicle door hinge']
Additive Manufactured Lightweight Vehicle Door Hinge with Hybrid Lattice Structure
Conference paper
https://repositories.lib.utexas.edu//bitstreams/f98a37b5-6776-4877-930b-6998f55c0a90/download
University of Texas at Austin
null
null
This paper presents an approach to finite element analysis of regulation to simulate mechanical behavior of door hinge with hybrid lattice structures.
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null
null
null
['Ivanova, Olga S.', 'Williams, Christopher B.', 'Campbell, Thomas A.']
2021-10-05T15:12:05Z
2021-10-05T15:12:05Z
2011
Mechanical Engineering
null
['https://hdl.handle.net/2152/88390', 'http://dx.doi.org/10.26153/tsw/15329']
eng
2011 International Solid Freeform Fabrication Symposium
Open
['Additive Manufacturing', 'nanomaterials', 'nanotechnology', 'AM technologies']
Additive Manufacturing (AM) and Nanotechnology: Promises and Challenges
Conference paper
https://repositories.lib.utexas.edu//bitstreams/b578771f-89c4-4e6a-bd1b-26e42d0cc50a/download
University of Texas at Austin
The narrow choice of materials used in Additive Manufacturing (AM) remains a key limitation to more advanced systems. Nanomaterials offer the potential to advance AM materials through modification of their fundamental material properties. In this paper, the authors provide a review of available published literature in which nanostructures are incorporated into AM printing media as an attempt to improve the properties of the final printed part. Specifically, we review the research in which metal, ceramic, and carbon nanomaterials have been incorporated into AM technologies such as stereolithography, laser sintering, fused filament fabrication, and three-dimensional printing. The purpose of this article is to summarize the research done to date, to highlight successes in the field, and to identify opportunities that the union of AM and nanotechnology could bring to science and technology.
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