摘要

A finite element model (FEM) of single-grain surface grinding of SiC has been established to understand the effects of the cutting-edge radius and grinding wheel speed on SiC chip formation. Based on the mechanic deformation behavior of SiC, the critical chip formation thickness and critical ductile-brittle transition thickness were found. Results obtained show that critical ductile-brittle transition thickness has a peak value at R-c = 1.25 mu m and v(s) = 80 m/s respectively. Normal grinding force increased firstly with the increasing cutting edge radius and then declined. The critical cutting edge radius R-c = 1.25 mu m and grinding wheel speed v(s) = 80 m/s were determined depending on the variation of critical chip formation thickness, critical ductile-brittle transition thickness, grinding force, ground surface quality. Finally, the simulation results were verified experimentally by an indirect single diamond grain scratching SiC ceramics test.