Combining Cold Spray and Solution Precursor Plasma Spray for Production of Improved Thermal Barrier Coating (TBC) Systems

Cold spray deposition of MCrAlY coatings and solution precursor plasma spray (SPPS) deposition of Ba(Mg_1/3Ta_2/3)O₃ perovskite have been separate topics of recent research and development works in the field of bond coat and topcoat for thermal barrier coatings (TBCs) used in gas turbine engines. In this study, the two techniques were combined aiming at producing the well-known columnar structured TBCs (typically achieved by electron beam-physical vapor deposition) with enhanced oxidation resistance provided by the unique cold spray bond coat microstructure. The latter was first characterized before and after the topcoat deposition to examine any potential microstructure modifications during the SPPS process. The effects of the bond coat morphology on the deposition and microstructure of the SPPS topcoats were investigated. Results show that topcoat characteristics can be tailored by modifying the SPPS parameter as well as bond coat surface conditions. The combination of dense cold sprayed bond coat and columnar SPPS topcoat is promising improved TBCs performance.