Hot corrosion behaviour of Pt modified aluminized NiCrAlYSi coating on a Ni-based single crystal superalloy.

Highlights • The hot corrosion behaviour of Pt modified aluminized NiCrAlYSi coating was investigated. • The Pt modified aluminized NiCrAlYSi coating showed superior hot corrosion resistance. • The addition of Pt suppressed the internal oxidation and sulfidation during hot corrosion test. • The outward diffusion of Ti in Pt modified aluminized NiCrAlYSi coating was inhibited. Abstract The hot corrosion tests of Pt modified aluminized NiCrAlYSi coating coated with mixed salt films of Na 2 SO 4 + K 2 SO 4 and NaCl + Na 2 SO 4 were carried out at 900 ℃. Compared to the aluminized NiCrAlYSi coating, the Pt modified aluminized NiCrAlYSi coating exhibited an enhanced hot corrosion resistance in these two types of mixed salts. The existence of Pt in the aluminized coating restrained the outward diffusion of substrate elements and effectively suppressed internal sulfidation and oxidation during hot corrosion test. The degradation mechanism of the coating in the corrosion condition was also discussed. [ABSTRACT FROM AUTHOR]