Preparation and oxidation performance of a low-diffusion Pt-modified aluminide coating with Re-base diffusion barrier

Abstract A low-diffusion (Ni,Pt)Al coating with Re-base diffusion barrier was prepared on a second-generation single-crystal superalloy via electroplating and gaseous aluminizing, in which the electroplating consisted of depositing Ni-Re and Pt, sequentially. Compared with normal (Ni,Pt)Al, cyclic and isothermal oxidation performances of the coating with Re-base DB were evaluated at 1100 °C in static air. It is indicated that the Re-base DB contributed to better oxidation resistance and lower inter-diffusion extent, where the thickness of secondary reaction zone decreased by 49 % after 1000 h isothermal oxidation. Mechanisms responsible for the improved oxidation performance and the role of Re-base DB are discussed.