工程陶瓷磨削表面残余应力及其分布研究

Research on Surface Residual Stress and Distribution of Engineering Ceramic Grinding

为了探究工程陶瓷磨削后表面残余应力以及残余应力的分布情况。通过磨削实验首先获得氮化硅与氧化锆陶瓷磨削后平行于磨削方向和垂直于磨削方向的表面残余应力,其次通过实验获得磨削表面下不同深度的残余应力分布情况,最后分析了表面残余应力与表面去除方式的关系。结果表明:表面残余压应力值随磨削参数的变化呈线性变化;随着磨削表面下深度的增加,残余应力分布由残余压应力向残余拉应力转变,后再转变为压应力并逐渐消失;平行于磨削方向的残余应力值要大于垂直磨削方向的残余应力值;氧化锆陶瓷残余应力值要大于氮化硅陶瓷的残余应力值;随着表面由塑性去除向脆性去除转变,表面残余压应力值逐渐减小,表面质量变差。在磨削加工中应选用较小的进给速度和磨削深度、较大的磨削速度使表面呈现较大的残余压应力,以此来获得较好的表面质量。

In order to explore the surface residual stress and residual stress distribution of engineering ceramics after grinding.First,the surface residual stress parallel to the grinding direction and perpendicular to the grinding direction of silicon nitride and zirconia ceramics after grinding were obtained through grinding experiments.Second,the distribution of residual stress at different depths under the grinding surface was obtained through experiments.At last,the relationship between the surface residual stress and the surface removal method was analyzed.The results show that the surface residual compressive stress value changes linearly with the changes of grinding parameters.As the depth under the grinding surface increases,the residual stress distribution changes from residual compressive stress to residual tensile stress,and then to compressive stress and gradually disappears.The residual stress value parallel to the grinding direction is bigger than the residual stress value perpendicular to the grinding direction.The residual stress value of zirconia ceramics is bigger than that of silicon nitride ceramics.As the surface changes from plastic removal to brittleness removal,the residual compressive stress value of the surface gradually decreases,and the surface quality deteriorates.In the grinding process,a smaller feed rate and grinding depth,and a larger grinding speed should be used to obtain the larger surface residual compressive stress,so as to obtain better surface quality.