Long term semiconducting and passive film properties of a novel dense FeCrMoCBY amorphous coating by atmospheric plasma spraying

The long term electrochemical corrosion behavior and passive film properties of a novel dense Fe48Cr15Mo14C15B6Y2 (at. %) amorphous coating were investigated using electrochemical measurement, Mott-Schottky test, effective capacitance model and XPS technique. The coating exhibited a superior corrosion resistance with a relative low current density of 5.305 x 10(-6) A cm(-2) even after 1000 h immersion in 3.5 wt% NaCl solution. The film composition changed slightly and made no difference to the corrosion behavior. Noting that point defect density in the passive film and film thickness played a dominant role in the corrosion resistance of the amorphous coating in chloride electrolyte. The enhanced long term corrosion resistance of the coating may be attributed to an inactive mass transport behavior in the passive film in the early immersion age.