基于弹性变形的超声磨削氧化锆陶瓷的粗糙度模型

A Roughness Model of Zirconia Ceramic Based on Elastic Deflection in Ultrasonic Grinding

针对磨粒突出高度随机分布的特点,结合砂轮型号,建立了磨粒突出高度的正态分布图。通过切削厚度概率密度函数建立了普通磨削和超声磨削的理论切削厚度公式,采用基于弹性变形的接触弧长,结合氧化锆陶瓷的材料特性,计算出基于弹性变形的最大未变形切削厚度。根据磨粒突出高度分布和表面粗糙度的算术平均偏差定义,建立了普通磨削和超声磨削的粗糙度模型。理论研究和实验结果均表明:使用超声磨削改善了工件的表面粗糙度。而该模型可以根据给定材料的性能有效测出其表面粗糙度。由于设计的磨粒形状单一,理论值比实际值小约20%。

According to the characteristic of random distribution of the outstanding height of abrasive and the type of grinding wheel, the figure of normal distribution of the outstanding height of abrasive is set up in this paper. The theory of cutting thickness formula of common grinding and ultrasonic grinding can be estab- lished by probability density function of cutting thickness. Using the contact length influenced by elastic deformation, combined with the material properties of zirconia ceramic, undeformed chip thickness affected by the elastic deformation could be calculated. According to the distribution of the outstanding height of abrasive and arithmetic average deviation definition of surface roughness, roughness model of common grinding and ultrasonic grinding is set up. Theoretical research and experimental results show that ultrasonic grinding improves the surface roughness of workpiece. The model can effectively predict the surface roughness according to the given material properties. Due to the design of single grinding grain shape, the theoretical value is about 20% smaller than the actual value.