A study on corrosion and corrosion-wear behavior of Fe-based amorphous alloy coating prepared by high velocity oxygen fuel method

In this study, the corrosion-wear behavior of a Fe-based amorphous alloy coating was analyzed using a pin-on-ring corrosion abrasion system. The Fe-based amorphous alloy coating was prepared by the high velocity oxygen fuel (HVOF) method. The purpose of this article is to study the corrosion-wear behavior of this Fe-based amorphous alloy coating in sea water. The dynamic potential polarization curve and friction coefficient measurement were used to explore the influence of different polarization potentials on the corrosion-wear of the Fe-based amorphous alloy coating. The corrosion behavior of the coating was also analyzed using SEM, TEM and XPS. The experimental results show that under low polarization potential, after the iron oxide is dissolved, the chromium element in the Fe-based amorphous alloy coating will form chromium trioxide to produce a passivation protective layer. However, when the polarization potential is increased, the chromium trioxide will begin to dissolve. Subsequently, the molybdate formed by the passivation layer of molybdenum dioxide and molybdenum trioxide will provide more effective corrosion resistance of this Fe-based amorphous alloy coating. In terms of corrosion-wear behavior, owing to high hardness of the Fe-based amorphous alloy, the wear rate under low polarization potential is very small. When the polarization potential increases, a softer passivation layer will be formed on the surface of the coating, which will cause the wear rate to increase. As the polarization potential is +200 mVSCE, the wear mechanism of the coating is mainly a plowing type. While at high polarization potential (+600 mVSCE), it changes to a corrosive wear type.