Comparative studies on the corrosion properties of a Fe–Mn–Al–Si steel and an interstitial-free steel

Recent developments in a group of super ductile Fe–Mn–Al–Si steels with high-manganese content demands for more research in the corrosion behavior of such steels. The corrosion properties of the Fe–Mn–Al–Si steel was studied in acidic (0.1 M H2SO4), alkaline (0.1 M NaOH) and chloride-containing (3.5% NaCl) environments, using immersion and polarization experiments and compared with that of interstitial-free (IF) steel. In acidic solution, the Fe–Mn–Al–Si steel exhibited significantly lower corrosion resistance than that of IF steel. Though the Fe–Mn–Al–Si steel showed lower corrosion resistance as compared to IF steel in chloride solution, the difference was not as substantial as observed in acidic medium. However, in alkaline solution, the Fe–Mn–Al–Si steel showed no significant difference in the corrosion resistance in comparison with that of IF steel, and moreover exhibited substantially high corrosion resistance than in acidic and chloride solution. The post-corrosion characterization studies showed higher corrosion attack of the Fe–Mn–Al–Si steel exposed to acidic solution as compared to that in alkaline and chloride solutions, which is consistent with the corrosion measurement data.