Simulation and experimental study on micro-cutting silicon carbide crystal with single grain diamond

In order to improve the brittle fracture and edge breakage of silicon carbide crystal in the micro-cutting process, a finite element simulation model of micro-cutting silicon carbide workpiece with diamond conical abrasive grain was established, and the selection range of micro-cutting depth and speed is determined through the pre-simulation model. Then the orthogonal experiment method is used to analyze the primary and secondary factors on the cutting force. Subsequently, the influence of single micro-cutting parameter on cutting effect is studied. Finally, with the help of Hertzian contact stress, the cutting force and quality of cutting edge were analyzed by scratching the silicon carbide crystal with a diamond tip. The maximum cutting depth is determined to be 1.5 μm by pre-simulation model. The cutting depth B is a significant factor affecting the main cutting force, cutting speed C and conical angle of diamond grain A are non-significant factors, and the optimal scheme of cutting parameters is B₁C₁A₂ (cutting depth 0.5 μm, cutting speed 76 m/s, conical angle of diamond grain 60°). It can improve the cutting stability by controlling the cutting depth, and appropriately improve the cutting speed can improve the cutting efficiency and ensure the cutting quality. The depth of pressing into the workpiece of diamond tip affects the friction coefficient, friction force and cutting force, and the 3D profiles of cutting edges are relatively clear, straight and clean.