Preparation of low-sulfur platinum and platinum aluminide layers in thermal barrier coatings

摘要

A method for preparing a coated nickel-base superalloy article reduces the sulfur content of the surface region of the metallic coating layers to low levels, thereby improving the adhesion of the coating layers to the article. The method includes depositing (52) a first layer (70) of platinum overlying the surface of a substrate (32), depositing (58) a second layer (76) of aluminum over the platinum, and final desulfurizing (60) the article by heating the article to elevated temperature, preferably in hydrogen, and removing (62) a small amount (78) of material from the surface that was exposed during the step of heating. A ceramic layer (40) may be deposited (64) over the desulfurized article. The article may also be similarly desulfurized at other points in the fabrication procedure. <IMAGE>