NASA Glenn's Environmental Barrier Coatings Technology Available to U.S. Industry

摘要

A major breakthrough in gas turbine engine performance (efficiency and emission) requires a new generation of hot section (combustor liners, vanes, and blades) structural materials having a temperature capability considerably higher than current metallic hot section structural materials. It is generally agreed that the temperature capability of Ni-base metals has reached their limit. Ceramic thermal barrier coatings are used to insulate metallic components, thereby allowing higher gas temperatures. But, the metallic component remains a weak link because the designer must allow for the possibility of coating loss from spallation or erosion. Si-based ceramics, such as silicon carbide (SiC) fiber-reinforced SiC ceramic matrix composites (SiC/SiC CMCs) and monolithic silicon nitride (Si_3N_4), exhibit superior high-temperature strength and durability, indicating their potential to revolutionize gas turbine engine technology.