A novel method for evaluating machining-induced damage in ceramic matrix composite

Subsurface damage (SSD) is one of critical problems in machining ceramic matrix composite (CMC). SSD distribution in CMC is too complicated to control. A suitable method for evaluating SSD is important to control the damage during machining CMC. However, current methods provide limited information of SSD. To recover more comprehensive information of SSD distribution in CMC, this study proposes a novel evaluation method. The method takes the damage type into consideration. Based on the damage type, a new concept of damage degree is used as evaluation index. The proposed method is experimentally demonstrated effective to evaluate SSD distribution in CMC. It could provide both damage depth and damage degree. Finally, the SSD model of CMC is established. The newly proposed method can provide more comprehensive understanding of SSD mechanism in machining CMC, which is important to high efficiency and low damage machining of CMC.