磨削力对HIPSN陶瓷磨削亚表面裂纹的影响

采用金刚石砂轮是磨削热等静压氮化硅(HIPSN)陶瓷最常用的加工方法,但是被磨零件亚表面常常伴随裂纹、崩碎等加工损伤,因此研究裂纹扩展一直是工程陶瓷的热点问题。对磨削加工后的HIPSN陶瓷亚表面裂纹进行探究,分析其在磨削加工过程中产生裂纹的原因以及去除机理,研究结果表明在磨削过程中对裂纹进行适当的控制,可以提高陶瓷零件的可靠性。设置单因素实验,对不同磨削参数下HIPSN陶瓷的磨削力进行测量,通过扫描电镜(SEM)对亚表面裂纹和表面形貌进行观察,分析磨削力对亚表面裂纹的影响。实验结果表明:磨削力随着砂轮线速度的增大而减小,随着工件进给速度和磨削深度的增大而增大;当磨削力变大时,陶瓷亚表面裂纹扩展程度增加,表面形貌变差。在粗磨加工HIPSN陶瓷时,可以通过减小工件进给速度和磨削深度,提高砂轮线速度的方法来降低裂纹的扩展程度,能够有效降低后续工艺的加工时间和难度,提高表面质量。

Effect of grinding force on subsurface cracks in HIPSN ceramic

The most common method for grinding HIPSN ceramics is using diamond wheels,but ceramic parts often emerge subsurface damage such as cracks and chipping,so research on the crack propagation is always a hot issue in engineering ceramics.Explored HIPSN ceramic subsurface cracks after grinding,analyzed the causes of cracks in grinding and the removal mechanism of HIPSN ceramics,the results show that proper control of cracks in the grinding process can improve the reliability of ceramic parts.By setting up a single factor experiment to measure HIPSN ceramic grinding force under different grinding parameters with the observation of subsurface crack and surface morphology by SEM,the effect of grinding force on subsurface cracks was analyzed.The experimental results show that the grinding force decreases with the increase of the grinding wheel linear speed,and increases with the increase of the feed speed and grinding depth,when the grinding force increases,the crack propagation degree of the ceramic subsurface increases and the surface morphology becomes worse.In the process of rough grinding HIPSN ceramics,the crack propagation can be reduced by reducing the feed speed and grinding depth,and increasing the grinding wheel linear speed,which can effectively reduce the processing time and difficulty of the subsequent process,improve the surface quality.