FEA Of Efficiency In Rotary Ultrasonic Drilling Of Engineering Ceramics

Ceramics used in engineering structure is called engineering ceramics, which has a serry of excellent pysical, chemical and biological property, it is used in electronics, aerospace industry, automobile and appending to new field. But it is the inherent brittleness and small inflating coefficient and high hardness of engineering ceramics which cause difficulty in machining, farther more, high manufaturing cost, hard to acchive high precision, high efficiency and high reliabitity. Rotary ultrasonic machining is a new machining method which differs with the traditional machining methods, and there are some advantages in machining engineering ceramics with this method, for instace, high precision, low surface roughness and long life of cutting tool. In rotary ultrasonic machining of engineering ceramics, the material removal results from compositive effect of brittle fracture and plastic flow, in which the brittle fracture is dominate. But because rotary ultrasonic machining is basing on micro removal of material, its efficiency is farely low.This article is basing on mechanism of rotary ultrasonic machining, in which FEA is emploied to analyse the efficiency of material removal in machining process, and simulate the drilling process, especially the brittle fracture of ceramics in impacting of abrasive article.First of all, to analyse the fracture process of ceramics, fracture mechanics of ceramics and existing cohesive law model are both cosidered, to reasonably choose the material property of ceramics and cohesive model.Secnodly in ABAUQS, the workpiece model is modified with scripting programming interface, cohesive elements was inserted into local area of meshed model of ceramics. In FEA reasonable analysis condition is choosed to simulate crack initiation and propogation of ceramics under impacting of abrasive article.Finally, in ABAQUS parametric modeling, existing experimental parameter is considered, to choose various ultrasonic amplitude, static load and engineering ceramics, to analyse relation between efficiency of rotary ultrasonic mechining and this parameters.