Abstract: Aiming at the problems of difficult processing and surface quality assurance of silicon nitride ceramics, a laser assisted turning method was proposed to process silicon nitride ceramics. The hardness and brittleness of the material were reduced by preheating the work piece by laser, and the surface quality of the ceramic work piece was effectively improved while cutting force was reduced. Firstly, the constitutive model of silicon nitride ceramics was established by finite element software ABAQUS/CAE, and the effect of laser on material removal in turning was analyzed. Laser assisted turning experiments were designed to study the influence of laser power parameters on cutting force and surface roughness, and the experimental results were compared with simulation analysis. The results indicate that with the increase of laser power, the cutting force and surface roughness decrease gradually. In the experiment, the cutting force decreases by 59.5% and the surface roughness decreases by 85%. The surface quality of laser-assisted processing is improved obviously. The results of experiment and simulation are consistent, which verifies the correctness of the model.
Key words: laser-assisted processing; silicon nitride; finite element simulation; cutting force; surface roughness