Susceptibility of minor alloying to corrosion behavior in yttrium-containing bulk amorphous steel

Minor alloying of yttrium to bulk amorphous steels can influence their corrosion resistance significantly. The corrosion behavior was investigated by using potentiodynamic polarization measurements, Mott-Schottky analysis and X-ray photoelectron spectroscopy (XPS). It showed that, in comparison with Y-free alloy, the stability of the passive film for 0.5 at.% yttrium alloy decreased sharply, whereas enhanced with more additions of yttrium. It is noticed that the corrosion resistance was correlated to semiconductor properties of the passive film. This is understood on the basis of the yttrium-doping-induced structural defect effects in the passive films. A probable way to further enhance the corrosion resistance of amorphous alloys is suggested. (C) 2008 Elsevier Ltd. All rights reserved.