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

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 نشر من قبل Songlin Yao
 تاريخ النشر 2018
  مجال البحث فيزياء
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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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