Patent ID: 6555179
Filing Date: 2003-04-29
Classification: C23C

Abstract:
A process for forming a thermal barrier coating system on a surface of a superalloy component, the method comprising the steps of:plasma spraying an MCrAlY bond coat on the surface of the component to have a surface roughness of at least 300 &mgr;inch Ra and a surface area ratio of at least 1.4; forming an inward diffusion aluminide layer in the surface of the bond coat using a vapor phase deposition process performed in a coating container and having process parameters that include a process temperature of about 925Â° C. to about 1040Â° C. and a process duration of four to twelve hours, the vapor phase deposition process using an aluminum donor containing 50 to 60 weight percent aluminum and an aluminum halide activator at a concentration of about 1.8 grams of activator per liter of coating container volume, the inward diffusion aluminide layer causing the surface of the bond coat to have an aluminum concentration of at least 30 weight percent while maintaining a surface roughness of at least 300 &mgr;inch Ra and a surface area ratio of at least 1.4; and depositing a ceramic layer on the bond coat.