Constitutive modeling for strain rate-dependent behaviors of nanocrystalline materials based on dislocation density evolution and strain gradient

Youyi Wu, Jianqiu Zhou, Shuhong Dong, Aosheng Hu, Lu Wang, Xuming Pang

科研成果: 期刊稿件文章同行评审

1 引用 (Scopus)

摘要

To evaluate the influence of strain rate on mechanical behavior of nanocrystalline (NC) materials, a phase mixture constitutive model composed of ordered grain interior phase and plastically softer grain boundary dislocation pile up zone phase was built. Because of dissimilar properties and mismatch between the two phases, dislocation density evolution controlling mechanism based on statistically stored dislocations and geometrically necessary dislocations was analyzed and extended to NC regime to consider their disparate effects. Based on the composite model, a new stress-strain constitutive relation for strain rate-dependent behaviors was firstly established based on dislocation density evolution and strain gradient theory. The calculated data were then compared with corresponding experimental curves and strong strain rate-dependent behaviors were exhibited, which indicated that the predictions kept in good agreement with experiments. Further discussions were presented for calculations of strain rate sensitivity and activation volume for NC Ni through the proposed model.

源语言英语
页(从-至)2982-2993
页数12
期刊Journal of Materials Research
29
24
DOI
出版状态已出版 - 20 10月 2014

指纹

探究 'Constitutive modeling for strain rate-dependent behaviors of nanocrystalline materials based on dislocation density evolution and strain gradient' 的科研主题。它们共同构成独一无二的指纹。

引用此