石英玻璃纳米压痕过程有限元模拟的正交实验分析(英文)

Orthogonal Test for Numerical Simulation of Nanoindentation Process of Quartz Glass

采用有限元方法模拟纳米压痕过程的影响因素较多,依据正交实验原理提出了确定这些影响因素重要性的一种新方法.选取石英玻璃材料的屈服应力、加工硬化指数以及纳米压头的尖端半径为影响因素,由于材料与压头间的接触摩擦对仿真结果影响不大,且试样在进行纳米实验前都要进行抛光打磨处理,故不考虑摩擦系数和表面粗糙度的影响.将仿真结果与实验结果相对误差的绝对值作为正交实验的指标,利用极差分析可知压头半径是影响模拟结果最重要的因素,屈服应力和加工硬化指数只对模拟出的残余深度有一定的影响.同时通过对比模拟和实验的载荷-位移曲线,得到实际压头尖端半径为300nm,石英玻璃的屈服强度为8GPa,加工硬化指数为0.3.

A novel method was presented in order to make sure the importance sequence of factors that affect nanoindentation process by finite element modeling（FEM） simulation,according to orthogonal test principle. The yield stress and the working hardening exponent of quartz glass,and the indenter＇ s tip radius were considered as effect factors, while ignoring the contact friction for its insignificance and the surface roughness of the specimen for the polishment before nanoindentation experiment. The target of the orthogonal test was the absolute value of relative error between simulation and experiment results. Using range analysis,the most important factor is found to be the indenter＇ s tip radius, while the yield stress and the working hardening exponent only have certain effect on the residual depth of load-depth curve. Meanwile,the real tip radius was found to be 300 nm, the yield stress was 8 GPa and the working hardening exponent was 0.3 by comparison between the simulation and the experimental load-depth curves.