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Abstract: Hot corrosion behavior of FGH96 powder metallurgy (P/M) superalloy in 25 % NaCl + 75 % Na2SO4 molten salts at 650, 700, and 750 °C was investigated in this paper. The methods of mass loss measurement, X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) were used here. The experimental results show that hot corrosion kinetics follows a square power law at 650 °C, while a linear one at 700 and 750 °C. The corrosion layer is detected to be composed of Cr2O3, NiO, and Ni2S3 at each temperature. The cross-sectional morphologies and corresponding elemental maps indicate that the corrosion layer is a stratified structure of oxide and sulfide. The results and analyses confirm that the hot corrosion mechanism of FGH96 P/M superalloy is a cooperate process of oxidation and sulfidation. Furthermore, the relatively higher concentrations of Cr, Co, and Ti provide better corrosion resistance to the attack of S and Cl−. [ABSTRACT FROM AUTHOR] more...