Corrosion and wear resistance of a Fe-based amorphous coating in underground environment

Fe-based amorphous coating with composition of Fe49.7Cr18Mn1.9Mo7.4W1.6B15.2C3.8Si2.4 has been prepared on a mild steel substrate by High velocity air fuel (HVAF) process. Microstructural characterization showed that the coating exhibits very dense structure with a porosity of 0.4% and compact bonding with the substrate. Polarization tests indicated that the coating presents superior corrosion resistance in simulated groundwater; EIS measurements revealed that although the solution penetrated into the coating defects, the corrosion process could slow down due to the plugging of the defects by corrosion products. It was also found that the coating possesses good dry wear resistance and fatigue wear mechanism dominated the friction process. The present results imply that the Fe-based amorphous coating is promising for industry applications in underground environment, such as the storage of spent nuclear fuels.