The corrosion resistance of a gas metal arc weld and its dependence on the oxide formed at different peak temperatures were investigated. Iron oxide was formed at the outermost surface of the heat-affected zone of welded specimen and the specimen heated to 500°C. A chromium oxide film formed at higher peak temperatures and the peak temperature rise increased the oxide thickness and Cr content within the oxide scale. The corrosion resistance of the specimens containing Fe oxide at the outer layer was reduced, while the specimens heated to 1100 and 1350°C had better corrosion resistance due to the strong passivity of the thick Cr oxide.

The optimal applied potential for the acceleration of the corrosion of hot-dip aluminized ferritic stainless steel in 5 mass% NaCl solution was investigated using electrochemical techniques (open-circuit potential measurement, electrochemical impedance spectroscopy, potentiodynamic-and potentiostatic-polarization tests). The feasibility of the use of the potentiostatic polarization test as a method for the acceleration of actual corrosion behavior was proved by the corrosion potential and the pitting potential of each layer in the potentiodynamic polarization test. The optimal applied potential for the potentiostatic polarization test was selected through comparison of the surface and electrochemical impedance spectroscopy analysis.