Effect of dislocation defects on the nano-scratching process of 4H–SiC

To investigate the influence of defects on the damage mechanism of 4H–SiC, this study primarily conducted molecular dynamics simulations of a single diamond abrasive indentation process and carried out subsequent nanoindentation experiments on 4H–SiC samples. The simulation and experimental results were compared, and the force–displacement curves showed consistent trends. On this basis, the scratching simulation of an ideal material and a single diamond abrasive particle containing 4H–SiC with dislocation defects was carried out to study the influence of internal dislocation (screw dislocation and edge dislocation) in 4H–SiC and its position on the material damage mechanism during scratching, and the development and evolution of internal dislocation were further analyzed. The results reveal that the presence of internal dislocations in the material is one of the causes of the formation of dislocation loops.