纳米ZrO_2陶瓷的超声振动延性域磨削特性研究

Study on Ductile Grinding Character of Nano ZrO_2 Ceramics using Ultrasonic Vibration Grinding

本文分析了纳米ZrO2陶瓷在普通和超声磨削状态下的裂纹扩展过程及延性去除机理;通过对不同磨削状态的磨削力及AFM和SEM对表面质量的观察,做了在普通和超声磨削状态下的对比试验,研究了临界延性磨削深度对磨削力及表面质量的影响关系;基于超声振动磨削过程及磨削力的分析,讨论了超声振动增加延性磨削深度的原因,最后通过AFM对延性域加工表面形貌的形成机理进行了观察。研究表明:超声加工能明显提高纳米ZrO2陶瓷的临界延性磨削深度,振动方向垂直于砂轮线速度方向时,其磨削效果要优于振动方向平行于砂轮速度方向的磨削效果。通过在延性域范围内磨削,超声加工能高效地获得纳米加工表面,超精密磨削表面是由不同幅值多种波形叠加的结果。

In this paper the crack extension course and ductile removal mechanics of nano ZrO2 ceramics were analyzed. On the basis of contrast test with or without ultrasonic vibration, the influence of critiCal ductile grinding depth on grinding forces and surface quality were studied by analyzing the grinding forces in different grinding state and surface quality observed by SEM and AFM. The reason for the increase of the critical grinding depth was discussed based on the analysis of grinding force and ultrasonic vibration course. At last, the formation mechanics of surface topography observed by AFM in ductile domain was analyzed. The research indicated that ultrasonic machining could increase the critical ductile grinding depth of nano ZrO2 ceramics obviously. The grinding effect when vibration direction perpendicular to wheel linear velocity superior to vibration direction parallel to wheel linear velocity. Through grinding in ductile domain, ultrasonic machining could obtain nano finished surface with high efficient. Uhraprecise grinding surface was the result superimposed by different amplitudes and multiple waveforms.