中文摘要：

通过分析硬脆材料脆性断裂去除机理和旋转超声加工特点,确定旋转超声加工时单颗磨粒的切削时间、切削深度、切削速度及切削轨迹长度,建立旋转超声恒进给率钻削硬脆材料的切削力数学预测模型。光学玻璃加工试验研究表明,切削力随进给速度的增大而增大,随主轴转速的提高而减小;在高进给速度条件下,切削力对主轴转速的变化更为敏感,在低主轴转速条件下,切削力对进给速度的变化更为敏感;从而很好地验证了已建立的切削力数学预测模型。旋转超声加工和普通加工的对比试验表明,旋转超声钻削加工可以有效降低切削力,一定程度上减小出孔崩边尺寸,从而提高加工效率、降低加工成本。根据旋转超声加工的表面粗糙度值略高于普通加工,提出硬脆材料脆性断裂去除时磨粒实际切削深度决定加工表面粗糙度的判断。

英文摘要：

The effective cutting time,cutting depth,cutting speed,and cutting length of single particle in rotary ultrasonic drilling are determined by examining mechanism of hard and brittle material brittle-fracture removal and analyzing characteristic of diamond tools＇ rotary ultrasonic machining.A mathematical model is presented to predict the cutting force in rotary ultrasonic drilling.The experimental investigations of optical glass show that cutting force increases with the increase of feedrate and decreases with the increase of spindle speed,and the effect of spindle speed on cutting force is much stronger at high feedrate and the effect of feedrate on cutting force is much stronger at low spindle speed,which verify the developed mathematical model.Comparative experiments on rotary ultrasonic drilling and conventional machining show that the former can reduce cutting force and machined hole exit chipping sizes,improve machining efficiency and lower machining cost.From the phenomenon that the surface roughness resulted from rotary ultrasonic drilling is higher than that from conventional machining,it is concluded that the particle effective cutting depth is the most important factor influencing surface roughness when hard and brittle material is removed by brittle fracture.