超声椭圆振动磨削ZTA的表面完整性研究

Research on surface integrity in ultrasonic elliptic vibration grinding of ZTA ceramics

针对改性氧化铝(ZTA)陶瓷的超声椭圆振动磨削,给出了磨粒的切削轨迹模型,讨论了其对加工精度的影响.通过试验获得了椭圆超声振动磨削对ZTA陶瓷的表面形貌的影响.被加工表面上可以观测到晶粒细化现象,几乎没有破碎发生,表明材料去除模式主要为塑性去除;与普通磨削的对比试验表明,表面粗糙度降低约30～40%.X-射线衍射分析表明被加工表面的相结构主要为α-Al2O3,和t-ZrO2,以及少量的m-ZrO2;普通磨削和超声椭圆振动磨削的表面上都观察不到非晶相.试验结果表明,ZTA的非弹性变形去除对表面完整性有重要影响.

The cutting trace of abrasive grain in ultrasonic elliptic vibration grinding was modelled,and its influence on surface finish improvement was discussed.Experiments of grinding conditions on the ground surface topography of ZTA ceramic workpiece was carried out.Experimental results showed that there were some crystal refinement and little fracture on the ground surface,which revealed that the plastic material removal mechanism was dominant in the process.Meanwhile the surface finish was improved by 30~40% compared with traditional grinding method.Furthermore,XRD analysis indicated that the surface phases were composed of α-Al_2O_3,t-ZrO_2 and a small amount of m-ZrO_2,and there was no amorphous phase on the ground surface both with and without ultrasonic assistance.Therefore,the removal mechanism of no-elastic deformation in ultrasonic elliptic vibration grinding of ZTA ceramics had important influence on the surface integrity.