High temperature spray dried composite abradable powder for combustion spraying and abradable barrier coating produced using same

摘要

An improved method of forming an abradable thermal barrier coating comprises providing a spray-dried powder of M-CrAlY and a solid lubricant, such as CoNiCrAlY-BN. Unlike powders provided for use with plasma spray guns, the powder is essentially free of polyester or other organic fugitive additives provided to increase porosity. The powder is applied using a combustion spray process and results in a M-CrAlY abradable coating that has an average porosity comparable to that of a plasma-applied coating but with smaller and more uniform pore distribution, and without requiring post-application heat treatments to remove fugitive materials. Deposition efficiency is also increased.