摘要
The residual stresses on the surface of the d ifferently ground and polished silicon nitride ceramics were measured using X-r ay diffraction and identified by SEM.The effect of the residual stress on the be nding strength was investigated.The investigations show that the grinding proces s can introduce subatantial tensile residual stresses up to 290MPa on the surfac e of silicon nitride ceramics,which has a significant effect on reducing the ben ding strength of the ceramics after grinding.Thus,in comparison with the ceramic s with a rough surface,the ceramics with a mirror image surface may have a lower strength.Polishing can smooth the residual stresses.When we evaluate the qualit y of the ceramic components after grinding,we must take residual stress into con sideration. The grinding methods and grinding conditions must be carefully selec ted in order to get the favorite residual stress as well as the surface smoothne ss.
The residual stresses on the surface of the d ifferently ground and polished silicon nitride ceramics were measured using X-r ay diffraction and identified by SEM.The effect of the residual stress on the be nding strength was investigated.The investigations show that the grinding proces s can introduce subatantial tensile residual stresses up to 290MPa on the surfac e of silicon nitride ceramics,which has a significant effect on reducing the ben ding strength of the ceramics after grinding.Thus,in comparison with the ceramic s with a rough surface,the ceramics with a mirror image surface may have a lower strength.Polishing can smooth the residual stresses.When we evaluate the qualit y of the ceramic components after grinding,we must take residual stress into con sideration. The grinding methods and grinding conditions must be carefully selec ted in order to get the favorite residual stress as well as the surface smoothne ss.
基金
Funded by the Key Research Foundation of China Education Ad ministration (No.02049)
