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Displaying 576 - 600 of 658

Flow-induced crystallization during materials extrusion additive manufacturing

September 10, 2018
Author(s)
Lily Northcutt, Sara Orski, Kalman D. Migler, Anthony Kotula
Material extrusion additive manufacturing processes force molten polymer through a printer nozzle at high (> 100 s-1) wall shear rates prior to cooling and crystallization. These high shear rates can lead to flow-induced crystallization in common polymer

SELF-IMPROVING ADDITIVE MANUFACTURING KNOWLEDGE MANAGEMENT

August 26, 2018
Author(s)
Yan Lu, Zhuo Yang, Douglas Eddy, Sundar Krishnamurty
The current AM development environment is far from being mature. Both software applications and workflow management tools are very limited due to the lack of knowledge to support engineering decision makings. AM knowledge includes design rules, operation

A SUPER-METAMODELLING FRAMEWORK TO OPTIMIZE SYSTEM PREDICTABILITY

August 25, 2018
Author(s)
Yan Lu, Douglas Eddy, Sundar Krishnamurty, Ian Grosse
Statistical metamodels can robustly predict manufacturing process and engineering systems design results. Various techniques, such as Kriging, polynomial regression, artificial neural network and others, are each best suited for different scenarios that

Diffusion in the Ti-Al-V system

August 23, 2018
Author(s)
Greta Lindwall, Kil-Won Moon, Zhangqi Chen, Michael J. Mengason, Maureen E. Williams, Justin Gorham, Ji-Cheng Zhao, Carelyn E. Campbell
Diffusion in the Ti-Al-V system is studied and a CΑLPHAD diffusion mobility description is developed. Diffusion couple experiments are used to obtain information of Al and V diffusion in the α phase. This includes diffusion paths at the temperatures 923 K

The Effects of Laser Powder Bed Fusion Process Parameters on Material Hardness and Density for Nickel Alloy 625

August 21, 2018
Author(s)
Christopher U. Brown, Gregor Jacob, Antonio M. Possolo, Carlos R. Beauchamp, Max A. Peltz, Mark R. Stoudt, M A. Donmez
The goal of this study was to investigate the relationship between mechanical and material properties (including density) of manufactured nickel super alloy (IN625) using a laser powder bed fusion process and three process parameters: laser power, hatch

Coupled experimental and computational study of residual stresses of additively manufactured Ti-6Al-4V components

July 30, 2018
Author(s)
Maria Strantza, Rishi Ganeriwala, Bjorn Clausen, Thien Q. Phan, Lyle E. Levine, D Pagan, Wayne King, Niel Hodge, Brown Donald
The production of metallic parts via laser-powder bed fusion (L-PBF) additive manufacturing is rapidly growing. To use components produced via L-PBF in safety-critical applications, a high degree of quality confidence is required. This qualification can be

Complementary Use of Optical Metrology and X-Ray Computed Tomography for Surface Finish and Defect Detection in Laser Powder Bed Fusion Additive Manufacturing

July 25, 2018
Author(s)
Jason C. Fox, Felix H. Kim, Zachary C. Reese, Christopher Evans
The development of additive manufacturing (AM) has allowed for production of high-value and complex parts that reduce time-to-market and cost to manufacture. A key benefit to the AM process is the capability to create lattice structures and highly complex

Measurement of Thermal Processing Variability in Powder Bed Fusion

July 24, 2018
Author(s)
Jarred C. Heigel, Eric P. Whitenton
Laser powder bed fusion (LPBF) is an additive manufacturing (AM) technology used to manufacture high-value metal parts. The layer-by-layer nature of the process allows complex geometries and internal features, such as conformal cooling channels, to be

Residual Stress in Additive Manufactured Nickel Alloy 625 Parts

June 29, 2018
Author(s)
Lindsey B. Bass, Justin L Milner, Thomas H. Gnaupel-Herold, Shawn P. Moylan
One of the key barriers to widespread adoption of additive manufacturing (AM) for metal parts is the build-up of residual stresses. In the laser-based powder bed fusion process, a laser selectively fuses metal powder layer by layer, generating significant
Displaying 576 - 600 of 658
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