单晶硅(111)晶面纳米压痕过程分子动力学仿真及实验(英文)

Molecular Dynamics Simulation and Experiments of Nano-Indentation of Single Crystal Silicon(111)Plane

为了研究脆性单晶材料单晶硅(111)晶面微观机械特征,应用分子动力学,对压痕过程进行仿真分析.本文应用平均势能和径向分布函数相结合方法对压痕过程进行考察.仿真结果表明,工件在压头附近的晶格结构发生变化.在仿真过程中通过确定工件内部的分界线来表明位错传播运动;在压痕结束后工件自身弛豫过程变形区域弹性恢复大约27%.,应用Hysitron公司的Triboindenter纳米原位压痕仪进行压痕实验,并把实验得到的材料压痕折合模量与分子动力学仿真计算结果进行比较,结果表明仿真的误差率小于31%.

To investigate micro mechanisms of brittle material single crystal silicon （111） plane from an atomic level, molecular dynamics （MD） simulation was used to analyze diamond nano-indention process. In this paper a new method was set up to investigate the indentation process through computing average potential and radial distribution function （RDF） of workpiece at the same time. The results show that lattices phase transformation occurs around the diamond indenter tip in the workpiece. It is also found that the deformed area has about 27% elastic recovery through comparing motions of demarcation line which represents the dislocation motions inner workpiece. The nano-indentation experiments were carried out by Triboindenter made by Hysitron Incorporated Company. Comparison of reduced modulus values between simulation and experiments is conducted and the results indicate that the simulation error rate is smaller than 31%.