Laser Machining of Ceramic Matrix Composites

Laser machining of dense silicon carbide/silicon carbide (SiC/SiC) woven composites and green silicon nitride/boron nitride (SNBN) fibrous monolithic composites has been investigated. Surface roughness profiles along the machined surfaces show that a lower arithmetic average surface roughness (Ra) for green SNBN ceramics and a Ra near the as-received value for silicon carbide/silicon carbide ceramic composites, can be achieved. Optical microscopy and SEM observations of heat-affected zones show very little thermal damage in either material.