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Displaying 201 - 225 of 333

SCALABLE THERMAL SIMULATION OF POWDER BED FUSION

October 1, 2020
Author(s)
Paul Witherell, Vadim Shapiro, Yaqi Zhang
Powder bed fusion (PBF) has become a widely used additive manufacturing (AM) technology to produce metallic parts. As the PBF process is driven by a moving heat source, consistency in part production, particularly when varying geometries, has proven

Chapter 8: Machine Performance Evaluation

September 22, 2020
Author(s)
Shawn Moylan
Machine performance evaluation is vital for objectively demonstrating that a machine can meet specification, standards and quality management system, and for allowing users to make informed decisions on how to best use their resources. Although additive

Electron and x-ray focused beam-induced cross-linking in liquids: Toward rapid continuous 3D nanoprinting and interfacing using soft materials

September 15, 2020
Author(s)
Tanya Gupta, Evgheni Strelcov, Glenn Holland, Joshua D. Schumacher, Yang Yang, Mandy Esch, Vladimir Aksyuk, Patrick Zeller, Matteo Amati, Luca Gregoratti, Andrei Kolmakov
Additive fabrication of biocompatible 3D structures out of liquid hydrogel solutions has become pivotal technology for tissue engineering, soft robotics, biosensing, drug delivery etc. Electron and X-ray lithography are well suited to pattern nanoscopic

Simultaneous High-speed X-ray Transmission Imaging and Absolute Dynamic Absorptance Measurements during High-power Laser-metal Processing

September 10, 2020
Author(s)
Brian Simonds, Jack R. Tanner, Alexandra B. Artusio-Glimpse, Paul A. Williams, Niranjan Parab, Cang Zhao, Tao Sun
During high-power laser metal processing, the absorbed light is intimately related to the molten metal cavity shape. For the first time, we directly and simultaneously observe this relationship by implementing state-of-the-art techniques of high-speed x

A NEIGHBORHOOD-BASED NEURAL NETWORK FOR MELT POOL PREDICTION AND CONTROL

September 1, 2020
Author(s)
Paul Witherell, Vadim Shapiro, Yaqi Zhang
One of the most prevalent additive manufacturing processes, the powder bed fusion process, is driven by a moving heat source that melts metals to build a part. This moving heat source, and the subsequent formation and moving of a melt pool, plays an

Nesting and Scheduling Problems for Additive Manufacturing: A Taxonomy and Review

August 21, 2020
Author(s)
Yosep Oh, Paul Witherell, Yan Lu, Timothy A. Sprock
With the trends of Industry 4.0 spanning physical and virtual worlds, Additive Manufacturing (AM) has been the mainstream for realizing complex geometries designed in computers. Meanwhile, a considerable number of AM studies have focused on effectively

Temperature-induced heteroaggregation in polydisperse portlandite suspensions

August 17, 2020
Author(s)
Edward Garboczi, Gaurav Sant, Iman Mehdipour, Narayanan Neithalath, Mathieu Bauchy, Samanvaya Srivastava, Sharu Bhagavathi Kandy
Temperature is well-known to affect the aggregation behavior of colloidal suspensions. This paper elucidates the temperature dependence of the rheology of portlandite (calcium hydroxide: Ca(OH)2) suspensions that feature a high ionic strength and a pH

Transient Laser Energy Absorption, Co-axial Melt Pool Monitoring, and Relationship to Melt Pool Morphology

August 16, 2020
Author(s)
Brandon M. Lane, Ivan Zhirnov, Sergey Mekhontsev, Steven E. Grantham, Richard E. Ricker, Santosh Rauniyar, Kevin Chou
Many recent and ongoing studies into the complex melt pool physics during laser powder bed fusion (LPBF) metal additive manufacturing (AM) process measure various aspects of energy transport surrounding the laser-induced melt pool, with focus on laser

Additive Manufacturing of Steels and Stainless Steels

August 1, 2020
Author(s)
Carelyn E. Campbell, Mark R. Stoudt, Fan Zhang
This work briefly reviews the classification of the different types of steels, the most common AM processes used for steel and the available powder feedstock. The characteristics of the as-built microstructure, including porosity, inclusions and residual

Data-driven characterization of computational models for powder-bed-fusion additive manufacturing

July 31, 2020
Author(s)
Yan Lu, Zhuo Yang, Paul W. Witherell, Wentao Yan, Kevontrez Jones, Gregory Wagner, Wing-Kam Liu, Jason C. Fox
Computational modeling for additive manufacturing has proven to be a powerful tool to understand the physical mechanisms, predict fabrication quality, and guide design and optimization. Varieties of models have been developed with different assumptions and

3D printed optical concentrators for LED arrays

July 19, 2020
Author(s)
Behrang H. Hamadani, Jonathan E. Seppala, Clarence J. Zarobila
Additive manufacturing methods based on photopolymerization offer a great potential for fabrication of high quality, highly transparent optical components. One appropriate use of these technologies is related to fabrication of parts that can be used in

Effects of laser-energy density and build orientation on the defect structure, microstructure and tensile properties of Inconel 718 parts manufactured with laser powder bed fusion

June 30, 2020
Author(s)
Dillon Watring, Jake Benzing, Nik Hrabe, Ashley Spear
This study investigates the processing-structure-property relationships of Inconel 718 manufactured by laser powder bed fusion. Three di erent build conditions were selected for the Inconel 718 specimens: 0 build orientation and 38 J/mm3, 0 build

Improving patient outcomes with regenerative medicine: How to move the needle forward in cell manufacturing, standards, 3D bioprinting, AI enabled automation, education and training

June 17, 2020
Author(s)
Carl Simon Jr., Josh Hunsberger, Claudia Zylberberg, Preveen Ramamoorthy, Thomas Tubon, Crystal Ruff, Ram Bedi, Kurt Gielen, Lynn Fisher, Jed Johnson, Priya Barankiak, Behzad Mahdavi, Michael Hadjisavas, Shannon Eaker, Cameron Miller
Regenerative Medicine Manufacturing Society (RMMS), is the first and only professional society dedicated specifically towards advancing manufacturing solutions for the field of regenerative medicine. RMMS' vision is to provide greater patient access to
Displaying 201 - 225 of 333