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arXiv · 1810.01954

Homogeneous Nucleation and Forest Hardening Result in Thermal Hardening Phenomenon in Shock Loaded BCC Metals

Songlin Yao·Xiaoyang Pei·Jidong Yu·Yuying Yu·Qiang Wu
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Abstract

Interpretation of thermal hardening phenomenon at high strain rate has recently become a critical problem in shock wave physics. In this letter, this problem is addressed from a viewpoint of dislocation generation, and a novel conclusion is gained that forest hardening induced by homogeneous nucleation (HN) results in thermal hardening behavior in a BCC metal significantly, apart from phonon drag mechanism. Through numerical simulations with a dislocation based crystal plasticity model, we have reproduced the experimental results quantitatively and predicted a thermal hardening behavior in other BCC metals, i.e., Mo, at higher temperature.

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Songlin Yao, Xiaoyang Pei, Jidong Yu, Yuying Yu, Qiang Wu. 2018-09-10. Homogeneous Nucleation and Forest Hardening Result in Thermal Hardening Phenomenon in Shock Loaded BCC Metals. https://arxiv.org/abs/1810.01954

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