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arXiv · 2303.13007

In-situ study of rules of nanostructure evolution, severe plastic deformations, and friction under high pressure

Feng Lin·Valery I. Levitas·Krishan K. Pandey·Sorb Yesudhas·Changyong Park
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Abstract

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. {\omega}-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 {\alpha}-Zr obtained with smooth and rough anvils are different, which causes major challenge in plasticity theory.

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Feng Lin, Valery I. Levitas, Krishan K. Pandey, Sorb Yesudhas, Changyong Park. 2023-03-23. In-situ study of rules of nanostructure evolution, severe plastic deformations, and friction under high pressure. https://doi.org/10.1080/21663831.2023.2231983

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