Influence of Al content on the microstructure and corrosion resistance in high manganese Fe–Mn–Al–C–Cr steels

Fe–Mn–Al–C low density high manganese steels have been developed as alternative materials for different engineering applications owing to their excellent combination of mechanical properties. However, some aspects such as the corrosion resistance need further investigation. The influence of Al addition on microstructure evolution and corrosion behavior of Fe–Mn–xAl–C–Cr steels was investigated in artificial seawater during 5 h of immersion. The materials were subjected to hot rolling followed by solubilization treatment for different time intervals. Corrosion behavior was studied by polarization curves and electrochemical impedance spectroscopy. After the solubilization process a fully austenitic structure with equiaxed grains and annealing twins was obtained for all the materials. The corrosion results indicated that the corrosion potential shifted to more noble values and the anodic dissolution decrease when the Al concentration increased.