The laminated composite of Fe–Al alloy and CrMo steel was fabricated by clad rolling to provide additional properties to the steel such as corrosion resistance, strength, and light weight. Three layered composite consisting of alloy/steel/alloy was succesfully fabricated using the process condition to satisfy the criteria for simultaneous deformation of different materials. The fabricated composite could be cold rolled to 120 μm thickness (99.8 % reduction), and wound to a coil without damage. The corrosion resistance of the composite in a sulfuric acid solution was comparable to that of monolithic CrMo steel, and it depends on the aluminium content of the Fe–Al alloy. The aluminium content dependence of the corrosion behavior is explained by the corrosion potential (Ecorr) of the Fe–Al alloy derived from the polarization curves in the solution. In order to improve the corrosion resistance of the composite, pre-oxidation treatment was conducted to form Al2O3 layer to protect the substrate. Analyses by XPS and SIMS show that the Al2O3 oxide fraction increases with the oxidization temperature and Al content of the alloy. The pre-oxidation treatment improved the corrosion resistance of the composite in a sulfuric acid solution. It is concluded that the effect of oxidation on the corrosion resistance is due to the formation of Al2O3 oxide and the Al2O3 fraction in the oxides.
Corrosion Behavior of AA 1100 Anodized in Gallic-Sulfuric Acid Solution
