Corrosion behavior of pure Cr with a solid NaCl deposit in O-2 plus water vapor

Abstract

The corrosion behavior of pure chromium with a solid NaCl deposit on its surface has been investigated in air or oxygen containing water vapor at 500-700 degreesC. Results indicated that, when pure Cr was corroded in air or in oxygen plus water vapor, the corrosion was restrained even at 700 degreesC because of the formation of a compact and uniform Cs2O3 protective scale. However, a solid NaCl deposit on its surface accelerated the corrosion of pure Cr in air or in oxygen plus water vapor significantly. A model of synergistic action to explain the effect of solid NaCl with oxygen and/or water vapor and on the corrosion of pure Cr is proposed.