Ni-Mo-Cr alloy corrosion in molten NaCl-KCl-MgCl2 salt and vapour

ABSTRACT The corrosion behaviours of Ni-Mo-Cr alloy samples immersed in NaCl-KCl-MgCl2 salt and vapour were investigated at 700.0 °C for 100 h. The surface layer of the corroded alloy in liquid molten salt exhibited slight Cr depletion. The alloy formed a loose double layer of Cr, Mo and Mg oxide in the vapour. The oxidation with Mg chloride in the salt vapour accelerated corrosion of the sample, and its Cr-depleted depth was nearly twice that of a sample immersed in liquid molten salt. The corrosion of an alloy by salt vapour must not be neglected in practical applications.