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Title: Rules of plastic strain-induced phase transformations and nanostructure evolution under high-pressure and severe plastic flow.
Severe plastic deformations under high pressure are used to produce nanostructured materials but were studied ex-situ. We introduce rough diamond anvils to reach maximum friction equal to yield strength in shear and perform the first in-situ study of the evolution of the pressure-dependent yield strength and nanostructural parameters for severely pre-deformed Zr. ω-Zr behaves like perfectly plastic, isotropic, and strain-path-independent. This is related to reaching steady values of the crystallite size and dislocation density, which are pressure-, strain- and strain-path-independent. However, steady states for α-Zr obtained with smooth and rough anvils are different, which causes major challenge in plasticity theory.  more » « less
Award ID(s):
2246991 1943710
NSF-PAR ID:
10495071
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
https://doi.org/10.48550/arXiv.2305.15737
Date Published:
Journal Name:
arXivorg
ISSN:
2331-8422
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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