On the efficacy of post-build thermomechanical treatments to improve properties of Zirconium fabricated using ultrasonic additive manufacturing

Journal Article · 24 August 2022 · Additive Manufacturing

DOI: https://doi.org/10.1016/j.addma.2022.103110 · OSTI ID:1890328

Massey, Caleb P. ^[1]; Gussev, Maxim N.  ^[1]; Havrilak, Cody J.  ^[1]; Seibert, Rachel L. ^[1]; Cakmak, Ercan  ^[1]; Nelson, Andrew T.  ^[1]

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1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Here, hot-isostatic pressing has been applied to Zirconium plate fabricated using the ultrasonic additive manufacturing (UAM) technique to enhance interfacial bond quality. Specimens heated to 800 C for 1 h at 100 MPa pressure showed grain growth across many prior foil-to-foil interfaces, thereby increasing foil adhesion. In addition to the material softening induced by a loss of Hall-Petch strengthening, premature failure of specimens loaded parallel to the build direction was observed. Premature specimen failure was attributed to the local delamination at prior foil-to-foil boundaries where grain growth was pinned by Ti impurities introduced during the UAM process via the interaction between a Ti-alloy buffer foil and the welded Zr-foils underneath. In addition, the presence of Ti along select foil interfaces resulted in the nucleation and growth of secondary (Zr,Ti)(Fe,Cr) laves phases during higher-temperature thermomechanical processing. Using a combination of micro-scale X-ray computed tomography, fractography, and in-situ digital image correlation, the effect of defects along prior foil-to-foil boundaries was revealed as delamination-assisted plasticity accelerated specimen failure in preferred tensile orientations. These findings underscore the importance of impurity control when optimizing weld quality of higher-strength material systems using ultrasonic welding.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Office of Defense Nuclear Nonproliferation
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 1890328
• Journal Information: Additive Manufacturing, Journal Name: Additive Manufacturing Journal Issue: A Vol. 59; ISSN 2214-8604
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English