Surface damage mechanism of WC/Co and RB-SiC/Si composites under high spindle speed grinding (HSSG)

Abstract

The surface damage mechanisms of WC/Co and Reaction-bonded SiC/Si (RB-SiC/Si) composites under high spindle speed grinding (HSSG) were investigated in the present work. Sharp edge loss and grit splintering were identified as two typical diamond wheel wear mechanisms. Plastic scratching grooves, Co extrusion and WC dislodgement were generated on the machined surface of WC/Co after grinding, while micro-pits of varied sizes at the phase boundaries and plastic scratching grooves were the main surface characteristics for RB-SiC/Si. Moreover, it was found that non-uniform surface finish at different radial positions resulted from the increase in material removal rate for both WC/Co and RB-SiC/Si, and the simulated results based on Soneys' model mostly corresponded with the measured outcomes. In addition, obvious relative wheel-workpiece vibration induced surface waviness was found, and its effect on the surface profile was analyzed for the wheel edge profile considered, which differed with that from single point diamond machining (SPDT).