Characteristics of Pulsed-Laser-Induced Layers with Cracks Prepared for SiC Grinding Processes

When grinding silicon carbide, surface and subsurface damage have a significant impact on the product's surface quality. One method to control the crack dimensions is laser irradiation on the SiC surface. The effect of this method on the grinding process is analyzed in this study. A series of experiments was carried out based on an orthogonal experimental design, with systematic adjustments made to laser parameters, including pulse energy (current), laser spot spacing, scanning times, and grinding process parameters. During the experiments, the grinding force was monitored by a dynamometer, and the specific grinding energy was calculated accordingly. Pulsed engraving laser modification effectively reduced the hardness of the ceramic surface layer by about 20%. The median and radial crack sizes induced by the laser in the subsurface layer ranged from 20.4 μm to 54.3 μm. This effectively inhibited further propagation of median and radial cracks during the grinding processes. Simultaneously, the tangential grinding force F_t was reduced by 30%. These conclusions were obtained through corresponding experiments that link surface roughness to laser power and grinding parameters. Using laser-induced controllable crack characteristics in the grinding process allow damage from surface and subsurface grinding to be controlled in brittle materials.