Experiment Study For Engineering Ceramics With Single Point Grinding Under Compressive Pre-stressing

Engineering ceramics,also called structure ceramics,have been widely used in modern manufacturing industries due to their superior properties,including chemical inertness,good wear resistance,high strength at high temperature,etc.However,it is difficult to machine them because of their hardness and brittleness,and the surface and subsurface damage produced by the machining process can be detrimental to the performance of the ceramic parts.Moreover,the cost of machining is great during ceramic manufacturing,account for up to45% of the components costs.Therefore,to realize high-quality surface and subsurface with high machining efficiency is still in the imperative.This thesis investigated the mechanism of decreasing the damage in pre-stress,and provided theoretical support for machining of engineering ceramics in pre-stress based on single point grinding.The main research works are summarized as following:1.The testbed about single point grinding in pre-stress was constructed,and the intension of wheel disk was checked with ANSYS.and also analyzed the motion curve of single point grinding,and then discussed the difference between single point grinding path and actual grinding path.2.The single point grinding on zirconia and aluminum ceramics in pre-stress were carried out.The surface/subsurface of zirconia and aluminum ceramics were observed.The effects of pre-stress and grinding depth on surface/subsurface crack propagation during engineering ceramics processing were discussed.3.The single point grinding tool was used to carried out a series of double scratch experiments under different machining parameters.The results indicated that the interaction between double scratches was closely dependent on the pre-stress,cutting depth and separation distance,the interaction between the double scratches could improve the material removal rate in some degree.The effect of double scratches on alumina ceramic is greater than that of zirconia ceramic under same processing parameters.In this paper,the mechanism of material removal and crack propagation of engineering ceramics was investigated by using single/double point grinding in pre-stress,which would provide a basic theory for obtaining a high efficiency and low damage of engineering ceramics processing.