Molecular dynamics simulations of tension-compression asymmetry in nanocrystalline copper

被引：37

作者：

Zhou, Kai ^{[1
]}

Shao, Shaofeng ^{[1
]}

Yao, Yijun ^{[1
]}

机构：

[1] Nanjing Univ Informat Sci Technol, Sch Phys & Optoelect Engn, Nanjing 210044, Jiangsu, Peoples R China

来源：

PHYSICS LETTERS A | 2017年 / 381卷 / 13期

基金：

中国国家自然科学基金;

关键词：

Tension compression asymmetry; Nanocrystalline copper; Molecular dynamics simulations; GRAIN-SIZE DEPENDENCE; MECHANICAL-BEHAVIOR; METALS; STRENGTH; DISLOCATIONS; DEFORMATION; PRESSURE; ALLOY; MODEL; CU;

D O I：

10.1016/j.physleta.2017.01.027

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Molecular dynamics simulations are used to investigate uniaxial tension and compression of nanocrystalline copper with mean grain sizes of 3.8-11.9 nm. The simulation resifts show an apparent asymmetry in the flow stress, with nanocrystalline copper stronger in compression than in tension. The asymmetry exhibits a maximum at the mean grain size of about 10 nm. The dominant mechanism of the asymmetry depends on the mean grain size. At small grain sizes, grain-boundary based plasticity dominates the asymmetry, while for large grain sizes the asymmetry mainly arises from the pressure dependent dislocation emission from grain boundaries. (C) 2017 Elsevier B.V. All rights reserved.

引用

页码：1163 / 1168

页数：6

共 35 条

[21] Rapid estimation of elastic constants by molecular dynamics simulation under constant stress [J].