An Indentation Theory Based on FEA Solutions for Material Property Evaluation

A new numerical approach of indentation theory is proposed by examining the finite element solutions based on the incremental plasticity theory with large geometry change. First the optimal data acquisition location is selected, where the strain gradient is the least and the effect of friction is negligible. This data acquisition point increases the strain range by a factor of five. Numerical regressions of obtained data exhibit that strain hardening exponent and yield strain are the two main parameters which govern the subindenter deformation characteristics. The new indentation theory successfully provides the stress-strain curve with an average error less than 3%.