Strain rate effect on material deformation and removal behavior during high speed scratching of 4H-SiC

The effects of strain rate on material deformation and tribology behavior of 4H-SiC are studied with high speed scratching tests, which represent typical processing modes of SiC wafers such as abrasive grinding/polishing. The results show that higher scratching speeds tend to induce more surface defects at the same scratching depth, which leads to the occurrence of ductile-to-brittle transition at smaller scratching depths. The relationship between the strain rate and scratching stress is analyzed, based on which a novel material model of 4H-SiC is proposed considering the strain rate effect. The research reflects a close correlation between scratching speeddependent stain rate and material deformation behavior of 4H-SiC, and it can provide guidance for process optimization during manufacturing of 4H-SiC components.