摘 要：采用多尺度准连续介质法分别模拟六种不同压头宽度下，铝薄膜纳米压痕初始塑性变形过程。在弹性变形阶段，矩形压头的宽度越大，对应载荷- 位移曲线的斜率越大，此时铝薄膜加载越困难。随着矩形压头宽度的不断增加，铝薄膜发生塑性变形所需的临界载荷越大，铝薄膜的纳米硬度呈现不断减小的趋势，铝薄膜呈现出明显的尺寸效应。铝薄膜中位错在压头两端正下方远离表面的地方形核，形成的全位错会迅速分解为两个Shockley 分位错，压头宽度越大，分位错之间的距离越大。
关键词：准连续介质法；纳米压痕；尺寸效应
中图分类号：TB383.2 文献标识码：A 文章编号：2096-4706（2018）10-0001-06
Multi-scale Simulation of the Nanoindentation of Aluminum Thin Film under theInfluence of the Indenter Size Effect
TAO Ye，WANG Zijie，DING Chunyuan
（School of Materials Science and Engineering，Hefei University of Technology，Hefei 230009，China）
Abstract：The multi-scale quasi-continuum method was used to simulate the initial plastic deformation process ofnanoindentation of aluminum film under six different indenter widths. In the elastic deformation stage，the width of the rectangularindenter is larger. The larger the slope corresponding to the load displacement curve，the loading of aluminum film is moredifficult. With the increase of the width of the rectangular indenter，the critical load required for plastic deformation of thealuminum film increases，and the nano-hardness of the aluminum film decreases. The size effect of the aluminum film is obvious.The dislocations in the aluminum film are located at the local core which is far away from the surface at the bottom of the indenter.The dislocations are rapidly decomposed into two Shockley dislocations. The larger the indenter width，the greater the distancebetween the dislocations.
Keywords：quasi-continuum method；nanoindentation；size effect
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作者简介：陶冶（1991.05-），男，汉族，安徽合肥人，硕士，研究方向：塑性成形。