Orthogonal test for numerical simulation of nanoindentation process of quartz glass

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.