Aqueous corrosion properties of Fe-Al and Fe-Cr-Al alloys

Properties of alloys containing up to 12% chromium and 10% aluminum have been determined. Anodic polarisation studies in 1N sulphuric acid and 1M sodium sulphate indicate that aluminum is beneficial in increasing the width of the passive region as long as the chromium content is controlled within certain limits; the effect on the height of the active-passive peak is, however, variable. Binary Fe-Al alloys have similar polarisation curves to mild steel with no major dependence on aluminum content. Pitting potentials in 1M sodium chloride were influenced by both the chromium and aluminum contents.