Evaluation of anisotropy of yield stress using surface in-plane displacements around an indentation residual imprint

This study proposed a practical method to evaluate the anisotropy of yield stress using spherical indentation with in-plane surface radial displacements around residual imprint measured by the digital image correlation method for metallic material without indentation curve. The relation between the ratio of yield stresses and the in-plane displacements developed on the surface was analyzed using finite element method (FEM) simulations for the materials with various mechanical properties. The development of radial displacements depends on the anisotropy of the yield stresses, and the ratio between radial displacement values on principal directions has a strong relation with the anisotropy of the yield stresses. An analytical solution for predicting the ratio of yield stresses was developed and it was verified using experimental data with anisotropic materials. The results for various metallic materials showed the feasibility of the proposed model with good accuracy.