The influence of dislocation climb on the mechanical behavior of polycrystals and grain size effect at elevated temperature
The influence of dislocation climb on the mechanical behavior of polycrystals and grain size effect at elevated temperature
复制标题
高温位错攀爬对多晶力学行为及晶粒尺寸效应的影响
DOI：
10.1016/j.ijplas.2014.06.002
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发表时间：
2014-10
影响因子：
9.8
通讯作者：
Tong, Jie
中科院分区：
文献类型：
--
作者：
Huang, Minsheng;Li, Zhenhuan;Tong, Jie
采用爬升辅助离散位错动力学(DDD)技术模拟了多晶铝拉伸过程中的力学行为。特别关注了位错攀移如何影响与选定的晶粒度有关的多晶铝在高温下的流动应力。在模拟中使用了由给定数量的颗粒组成的周期性代表单元(PRC)。结果表明，在所考虑的高温下，位错攀移对多晶的力学行为起着重要的作用。位错攀移通过缓解位错在晶界的堆积，显著降低了流动应力和硬化速率，增加了位错密度。此外，位错攀移显著减弱了晶粒度对多晶铝屈服应力的影响，尤其是当晶粒度落在亚微米范围内时。另一个有趣的结果是，在高温下，当同时考虑位错攀移和滑移时，尽管材料的强度随着加载速度的增加而增加，但晶粒度对所施加的应变率的影响似乎并不显著。
The mechanical behavior of a polycrystalline aluminum in tension was modeled using a climb-assisted discrete dislocation dynamics (DDD) technique. Special focus was on how dislocation climb influences the flow stress of the polycrystalline aluminum with regard to selected grain sizes at elevated temperature. A periodical representative cell (PRC) consisting of given number of grains was used in the simulations. Results showed that, at the high temperature considered, dislocation climb plays an important role in defining the mechanical behavior of the polycrystalline crystal. Specifically, dislocation climb decreases significantly the flow stress and hardening rate while increases the dislocation density by relieving the dislocation pile-ups against the grain boundaries (GBs). In addition, the grain size effect on the yield stress of polycrystalline aluminum is significantly weakened by dislocation climb, especially when the grain size falls in the range of submicron. Another interesting result is that, at high temperature, when both dislocation climb and glide are considered, the grain size effect seems to be insignificant with regard to the applied strain rate, although the strength of material increases with enhanced loading rate.
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影响因子：
6
作者：
H. Fan;Zhenhua Li;Minsheng Huang
通讯作者：
H. Fan;Zhenhua Li;Minsheng Huang
影响因子：
9.8
作者：
Minsheng Huang;J. Tong;Zhenhua Li
通讯作者：
Minsheng Huang;J. Tong;Zhenhua Li
影响因子：
9.4
作者：
B. Szajewski;S. Chakravarthy;W. Curtin
通讯作者：
B. Szajewski;S. Chakravarthy;W. Curtin
影响因子：
9.4
作者：
Misra, A;Hirth, JP;Hoagland, RG
通讯作者：
Hoagland, RG
DOI：
10.1007/bf02661312
发表时间：
1972-01-01
期刊：
METALLURGICAL TRANSACTIONS
影响因子：
--
作者：
HIRTH, JP
通讯作者：
HIRTH, JP