Coupling of double grains enforces the grinding process in vibration-assisted scratch: Insights from molecular dynamics

Coupling of multiple abrasive grains is crucial for the efficiency in the grinding process and grinder design. Here the coupling effect in a double-grain model in vibration-assisted scratch of single-crystal silicon carbide (SiC) have been investigated using the molecular dynamics simulations for both simultaneous and sequential scratch processes. The coupling between the double abrasive grains affect the scratch force, stress, amorphous layer and surface morphology. The reduction ratios of tangential and normal force and the influenced material volume show that the critical distance for the inhibition of the coupling of vibration-assisted scratch is significantly greater than that in conventional scratch. The change of overlap ratio can reflect the change trend of the scratch force reduction ratio. In the vibration-assisted grinding, the increase of overlap ratio also intensifies the coupling of the abrasive grains, resulting in faster material removal, smaller scratch force and better surface finish. Insights obtained through the molecular dynamics analysis in this work into the coupling effects of abrasive grains in the vibration-assisted grinding process is believed to be beneficial in the development of grinding wheels and the optimization of machining processes.