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Title: Quantifying residual stress in Helium-implanted surfaces and its implication for blistering
Helium implantation in surfaces is of interest for plasma-facing materials and other nuclear applications. Vanadium as both a representative bcc material and a material relevant for fusion applications is implanted using a Helium ion beam microscope, and the resulting swelling and nanomechanical properties are quantifed. These values are put in correlation to data obtained from micro-residual stress measurements using a focused ion beam-based ring-core technique. We found that the swelling measured is similar to literature values. Further, we are able to measure the surface stress caused by the implantation and fnd that it approaches the yield strength of the material at blistering doses. The simple calculations performed in the present work, along with several geometrical considerations deduced from experimental results confrm the driving force for blister formation comes from bulging resulting mainly from gas pressure buildup, rather than solely stress-induced buckling  more » « less
Award ID(s):
1807822
NSF-PAR ID:
10258186
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Journal of Materials Research
ISSN:
0884-2914
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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