A study of ultra-precision processing mechanism of SiC crystals by MD simulation

Silicon carbide (SiC) is an ideal semiconductor material, renowned for its excellent electrical properties. However, its exceptional hardness and brittleness make it particularly challenging to process. Ultra-precision machining of SiC is not only time-consuming but also cost-intensive. Additionally, the machining phenomena are difficult to analyse, and the underlying mechanisms are challenging to elucidate using conventional observation methods. Molecular dynamics (MD) simulation, a recent advancement, offers a novel approach for observing atomic-level phenomena, making it highly suitable for studying the mechanisms of ultra-precision machining. This study investigates the ultra-precision grinding mechanisms of SiC using MD simulations and examines the impact of different abrasive grit shapes on the machining phenomena of 4H-SiC. Furthermore, the variations in defect removal efficiency across different abrasive grits are explored. The results show that the presence of cracks leads to brittle material removal during ultra-precision grinding. Sharp conical abrasive grits should be avoided to prevent ineffective defect removal and surface degradation.