Characterizing The Internal Morphology of Transition Regions in Large-Scale Extrusion Deposition Additive Manufacturing

Conference · Wed Dec 01 04:00:00 EST 2021

OSTI ID:1846520

Brackett, James ^[1]; Hussein, Zaky ^[2]; Charles, Elijah ^[2]; Smith, Tyler ^[1]; Hassen, Ahmed ^[1]; Kim, Pum ^[1]; Kunc, Vlastimil ^[1]; Duty, Chad ^[1]

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1. ORNL
2. University of Tennessee, Knoxville (UTK)

A dual-hopper feed system that was developed for the Big Area Additive Manufacturing (BAAM) system allows for transitioning between different materials while maintaining continuous deposition. This technique creates a step-change in material feedstock by switching the pellet feeding system to alternate which hopper is currently supplying material, allowing for multi-material construction. The step-change in feedstock material produces a transition region that is characterized by a compositional gradient and blended internal morphology. Initial cross-sectional imaging of the transition region revealed a non-homogenous blend of materials with distinct domains of each material, likely due to incomplete mixing within the screw. This study used a carbon fiber reinforced acrylonitrile butadiene styrene (CF-ABS) and an unfilled ABS to characterize the internal structure and to correlate it to mechanical performance by tracking microhardness across cross-sections of the transition region.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE; USDOE Office of Energy Efficiency and Renewable Energy (EERE)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1846520
• Country of Publication: United States
• Language: English