Erosion behavior of SiC fiber-SiC matrix composites

The erosion resistance of an SiC-SiC composite was determined at 25 and 850 °C. It was determined that the erosion rate related inversely to the density and hardness of the composite. The material loss at 25 °C was by a cracking and chipping mechanism for both the matrix and the fibers. The erosion rate of the composite at 850 °C was an order of magnitude lower than it was at 25 °C and the rates of loss at all particle impact angles were lower than occurred for several ferritic and austenitic chromium steels tested at comparable conditions. The improvement in the erosion resistance at 850 °C compared to 25 °C is thought to be due to the increased ductility of the composite.