Material removal and interactions between an abrasive and a SiC substrate: A molecular dynamics simulation study

Abstract In this paper, molecular dynamics simulation is applied to inspect the effect of sliding, rolling, vibrating and rolling plus vibrating movements of a diamond abrasive on nanotribology properties of a 4H–SiC substrate. The effect of the abrasive size, depth of polishing, sliding speed, rolling, and vibrating movements on material removal are surveyed. For the first time in literature, the rolling in x-axis, vibrating in horizontal direction, and rolling combined with vibrating movements are considered. The results present that a bigger abrasive mostly gains a lower asperity height and a higher number of atoms removed. The rolling motion in the x-axis achieves the highest number of atoms removed while the rolling motion in the reverse z-axis achieves the lowest asperity height. In the vibrating movements, the horizontal vibrating movement creates a lower asperity and a higher number of atoms removed than the vertical and the rolling plus vibrating motions. The number of atoms eliminated does not sensitive to the vibrating amplitude and the vibrating frequency. Moreover, a multi-asperities model is constructed to estimate the global-scale surface of the substrate after removing the asperities. The asperity height is removed effectively by the rolling plus vibrating motion. The surface roughness produced by rolling in x-axis movement and vibrating motions are better than other motions. This model also points out the saturated behavior of all types of movements, except the rolling plus vibrating motion. The interactions between the abrasive and the asperity could create a lengthened asperity, amorphization, new C–C bonding, clusters of atoms adhered on the abrasive surface, a high temperature at the interface, atomic strain, cleavage event and fly away atoms.