Numerical Study of the Effect of Materials’ Plastic Behavior on Equibiaxial Residual Stress Measurement using Indentation

Indentation is a new method for estimating residual stress. The plastic behavior of the materials under study can affect indentation parameters and, thus, influences the results of residual stress measurement. In this paper, the effect of yield stress and work-hardening exponent on the accuracy of residual stress measurements in steels and aluminums was studied. Results showed that, for materials with a low strain-hardening exponent and yield strain, Lee’s model is applicable; for materials with relatively high amounts of strain-hardening exponent and yield strain, Wang’s model is more accurate; and for materials with a medium range of strain-hardening exponent and yield strain all three models can be applied. It was also found that the stresses being tensile or compressive can affect the accuracy of the calculated results for each model. The applicable range of each model is represented in the article.