An analytical model to predict the depth of sub-surface damage for grinding of brittle materials

Abstract

This paper proposes an analytical model for predicting grinding-induced sub-surface damage depth in a silicon wafer. The model integrates the dislocation kinetics for crack initiation and fracture mechanics for crack propagation for the first time. Unlike other conventional models, the proposed model considers the effects of strain rate on damage depth and the dynamically changing metastable phase change properties. The model is verified by grinding experiments and a comparison of theoretical and experimental results shows a good quantitative agreement. It is found that increasing grinding speed and decreasing depth of cut cause a higher strain rate so as to enhance material brittleness, which is favorable to achieving low sub-surface damage. These findings will pave a way towards optimizing the grinding parameters and greatly improving the production efficiency of hard and brittle materials.