Comparison of the corrosion resistance behaviour for two metal-metal glassy alloys in neutral solution with chloride impact

The electrochemical behaviour of bulk glassy Fe78Co9Cr10Mo2Al1 and Fe49Co49V2 alloys was investigated using electrochemical techniques with different concentrations of Na2SO4 solution (0.25, 0.5 and 1.0 M). The alloys surfaces were characterized by various morphology and composition techniques. The corrosion rate of the two alloys is inversely proportional to the concentration of Na2SO4 solution. The VX9 alloy exhibited spontaneous production of a good passive layer in Na2SO4 solutions as a response to the presence of protective elements, such as Cr (10%), Mo (2%) and Al (1%). No passivation occurred on the surface of the VX50 alloy, with only salt precipitating on it. Adding chloride reduces the resistivity of both alloys as it is a localized attack.