Abstract:Ultrasonic fine atomization polishing of silicon nitride ceramic substrate was carried out by orthogonal tests,and the effect of polishing parameters(slurry flow rate,polishing pressure,polishing speed) on the polishing rate and surface roughness of the silicon nitride substrate was studied.In order to realize the high efficiency and high quality machining of silicon nitride ceramics,with the material removal rate and surface roughness of polished silicon nitride ceramics as the evaluating indicators,the optimal parameter combination was obtained according to the results of orthogonal experiments,and the polishing effect by optimal parameters was compared with traditional polishing effect.The results show that,for the three kinds of polishing parameters studied,the polishing liquid flow has the largest influence on the material removal rate,following by polishing pressure and polishing speed,while the polishing speed has the largest influence on the surface roughness of the silicon nitride substrate,following by polishing liquid flow and polishing pressure.Under the same experimental conditions,the material removal rate and surface roughness by fine atomization polishing are close to those of traditional polishing,but the amount of polishing liquid used for fine atomization polishing is only 125% of that used for traditional polishing,which avoids the waste of resources effectively.