Variation of strain rate sensitivity of an aluminum alloy in a wide strain rate range: Mechanism analysis and modeling

影响因子：6.371

DOI码：10.1016/j.jallcom.2016.07.077

所属单位：Northwestern Polytechnical University

发表刊物：Journal of Alloys and Compounds

关键字：Strain rate sensitivity High strain rate forming Mechanisms Aluminum alloy

摘要：The significant variation of strain rate sensitivity (SRS), i.e. the non-linear characteristics of SRS, within wide strain and strain rate ranges in high strain rate forming (HSRF) leads to the complexity of constitutive behaviors of aluminum alloys. Therefore, in order to achieve accurate simulation of HSRF process, a panoramic description of the SRS variation and related mechanisms are required within wide ranges. To address this problem, taking 5A06 aluminum alloy as an example, three distinct SRS zones were determined at 0.001 s−1–5000 s−1 in the present work, including quasi-static negative SRS zone (Zone-I), positive SRS zone at dynamic strain rate (Zone-II) and negative SRS zone at high strain and strain rate (Zone-III). Then, the mechanism for that in Zone-II is attributed to the conversion from dislocation glide to viscous drag through thermal activation analysis. In Zone-III, the dominant mechanisms are the change of dislocation configuration from dislocation cells and dislocation bands to subgrains in adiabatic shear bands in compression and to the increasing volume fraction of voids in tension, respectively, which is proved by SEM and TEM observations. Consequently, the effect of dislocation evolution on the SRS was quantitatively characterized and the nonlinear rate dependent stress responses of the aluminum alloy in a wide strain rate range were captured.

合写作者：X. Yao

第一作者：S.L. Yan

论文类型：期刊论文

通讯作者：H. Yang,H.W. Li

学科门类：工学

文献类型：J

卷号：688

页面范围：776-786

是否译文：否

发表时间：2016-12-15

收录刊物：SCI、EI

发布期刊链接：https://www.sciencedirect.com/science/article/pii/S0925838816321107?via%3Dihub

附件：

variation of strain rate sensitivity.pdf