A Crystal Plasticity Investigation of Residual Stress by Incorporating Pile-up Effect in Nanoindentation

Nanoindentation has been found to be an efficient way to quantify residual stress. Based on the measured load–displacement during indentation, residual stress is commonly evaluated using the Suresh method. However, this method relies on mathematical corrections to the contact area function, which can possibly underestimate the true contact area due to unavoided pile-up in the indented profile. In this work, an energy-based analytical solution for residual stress evaluation is proposed to explicitly incorporate the pile-up effects using a Berkovich indenter. The predicted results show close agreement with those from crystal plasticity finite element method (CPFEM), while being slightly lower than those obtained using the Suresh method. The proposed method is suggested to be applicable for indentation depth exceeding 150 nm, as shallower indentations are more susceptible to size effects.