On the deformation mechanism of 6H-SiC under the nanogrinding of multiple abrasive grains

This paper investigates effects of nanogrinding-induced defect on deformation of 6H-SiC with the aid of molecular dynamic analyses. It was found that nanogrinding perfect 6H-SiC will unavoidably bring about a damage layer containing amorphous phase transformation and discrete dislocations. The damage will significantly affect the subsequent deformation, surface morphology, grinding force and coefficient of friction. Under the interactions with the consecutive abrasives, the deformation mechanism of 6H-SiC transits from plastic flow within the amorphous layer to the propagation of existing dislocations and finally to the nucleation of new dislocations. The remnant amorphous layer on the ground surface can be minimized when the grinding depth of the subsequent grains is to be less than the thickness of the first amorphous layer.