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arXiv · 2305.15737

Rules of plastic strain-induced phase transformations and nanostructure evolution under high-pressure and severe plastic flow

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

Rough diamond anvils (rough-DA) are introduced to intensify all occurring processes during an in-situ study of heterogeneous compression of strongly pre-deformed Zr in diamond anvil cell (DAC). Crystallite size and dislocation density of Zr are getting pressure-, plastic strain tensor- and strain-path-independent during {\alpha}-{\omega} phase transformation (PT) and depend solely on the volume fraction of {\omega}-Zr. Rough-DA produce a steady nanostructure in {\alpha}-Zr with lower crystallite size and larger dislocation density than smooth-DA, leading to a two-time reduction in a minimum pressure for {\alpha}-{\omega} PT to a record value 0.67 GPa. The kinetics of strain-induced PT unexpectedly depends on time.

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Feng Lin, Valery Levitas, Krishan Pandey, Sorb Yesudhas, Changyong Park. 2023-05-25. Rules of plastic strain-induced phase transformations and nanostructure evolution under high-pressure and severe plastic flow. https://arxiv.org/abs/2305.15737

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