Effect of Ru in the underlying superalloy on isothermal oxidation performance of Pt-Al coating

Pt modified aluminide (Pt-Al) coatings were prepared on the third- and fourth-generation single crystal superalloys by electroplating Pt and successive aluminization. The isothermal oxidation behaviors of both coatings were investigated at 1100 ℃ for 350 h. The results showed the Pt-Al coating on the fourth-generation single crystal superalloy had superior oxidation resistance. Ru in the fourth-generation single crystal superalloy diffused into Pt-Al coating during isothermal oxidation and increased spallation resistance of oxide scale. The effects of Ru on the anti-spallation property of oxide scale and the interdiffusion between coating and substrate were discussed. The diffusion process of Ru was investigated.