SiC_(f)/SiC陶瓷基复合材料单颗磨粒磨削试验研究

Experimental Study of Single Grain Grinding for SiC_(f)/SiC Ceramic Matrix Composites

对碳化硅纤维增强碳化硅陶瓷基复合材料(SiC/SiC)进行了单颗磨粒磨削试验,研究了脆性去除模式下磨削中侧边崩碎规律。研究结果表明:磨削SiC基体时,基体内裂纹易引发磨削中大块侧边崩碎;磨削纤维时,侧边崩碎宽度随纤维与磨削方向夹角的增大而增大;磨削90°纤维时,提高磨削速度可减小侧边崩碎程度;以50 m/s和90 m/s的磨削速度磨削造成的侧边崩碎宽度比以20 m/s磨削时的侧边崩碎宽度分别小30%和60%;在试验参数范围内,增大磨削用量不会增大磨削中侧边崩碎程度,但可以提高材料去除率。

The single grain grinding tests of silicon carbide fiber-reinforced silicon carbide(SiC/SiC)ceramic matrix composites were conducted to investigate the side chipping characteristics under the brittle removal mode.The results show that when grinding SiC matrix,the cracks in the matrix easily lead to the side chipping of large blocks.When grinding fibers,the widths of side chipping increase with the increasing of the angles between fiber and grinding direction.When grinding the 90°fiber,increasing grinding speed may decrease side chipping degree.The side chipping widths caused by grinding at 50 m/s and 90 m/s are as 30%and 60%smaller than that by grinding at 20 m/s,respectively.In the ranges of testing parameters,increasing the grinding parameters may not increase the side chipping degree,but may improve the material removal rate.