Insight into the Corrosion Resistance of Mo-added NiCrBSi Coating in Simulated Waste Incineration Environment

The corrosion resistance of Ni40AA and Ni40AA-Mo coatings on 304SS substrate was evaluated in molten NaClNa2SO4-KCl-K2SO4 salts at 600 degrees C. In the oxidizing-chloridizing environment, results showed that Cr or Cr-rich oxides would react with molten salts and generate chlorides or chromates (Na2Cr2O4; K2CrO4). After adding Mo, the dissolved Cr in soluble corrosion products was significantly reduced. Mo substituted Cr to react with molten salts and reduced the depletion of Cr, which benefited the accumulation of Cr-rich oxides. Therefore, adding Mo enhanced the corrosion resistance of Ni40AA, reducing the corrosion weight gain by approx. 50% and the thickness loss by 1/3.