Effect of Temperature and Velocity on Microparticle Erosion/Deposition into Environmental-Barrier-Coated Ceramic Matrix Composite for Aeroengines

Ceramic matrix composites (CMCs), especially SiC/SiC, have garnered significant attention owing to their remarkable mechanical properties at higher temperatures. For the protection of the substrate from oxidation, the SiC/SiC CMCs inherently require environmental barrier coating (EBC). Because aeroengines must function under a wide range of conditions and environments, the coated CMC must be sufficiently resistant to various damage modes. Among these, the effect of microparticles is one of the limiting factors for the durability and performance of components, particularly when the engine is operated in dusty areas. The main goal of this experimental research is to investigate and determine the surface damage behavior of the coated CMC caused by micro-sand particles. The data were surveyed across a fairly broad range of exposed temperatures and velocities, and covered conditions relevant to advanced hot section designs. In the experiments, silica or alumina sand entrained in the gas stream was jet-blasted from the nozzle and then impinged on the target CMC + EBC coupon. Owing to the broad testing range, the damage mode and extent of damage varied considerably by condition. The obtained data were then reorganized and compared with several previously proposed particle impact models. This is to first understand and obtain a complete picture of all the probable consequences in the expected design and off-design conditions and, second, to determine the validity of, and deviations from the conventional modeling with the present CMC + EBC material, which will be useful in the next component design phase.