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  • Solidification crack propagation and morphology dependence on processing parameters in AA6061 from ultra-high-speed x-ray visualization
Title: Solidification crack propagation and morphology dependence on processing parameters in AA6061 from ultra-high-speed x-ray visualization
Solidification or hot cracks are commonly observed defects in a number of metal alloys and may lead to deterioration of additively manufactured parts quality. In this study, ultra-high-speed x-ray radiography experiments enable the observation and characterization of bundles of hot-cracks that form in monobloc AA6061 substrate. The crack bundles are related to meltpool characteristics and pore formation. Crack propagation rate is also presented for the case of a crack that initiates from a pore. Two types of relevant pore formation are also described, namely keyhole porosity and crack-remelting porosity. The results of this study are expected to facilitate the validation of theoretical and numerical models of solidification cracking.  more » « less
Award ID(s):
1905910
PAR ID:
10233353
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Additive manufacturing
Volume:
42
ISSN:
2214-7810
Page Range / eLocation ID:
101959
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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