Corrosion Resistance of Artificial Passive Film and Real Passive Film on Fe-Ti Alloy

Abstract

The corrosion resistances of Fe20~-TiO2 artificial passive film and real passive film on the sputter-deposited Fe-Ti alloy films were examined in acid solutions. The Fe203-TiO2 films containing less than XTi=0.70 have a spinal structure, the films containing more than XTi=0.70 have an amorphous structure. The dissolution rate of the Fe203-TiO2 films in 5 M HCI decreased with an increase in the titanium cationic fraction in the films. The FezO3-TiO2 films dissolved at cathodic potentials in 1 M H2SO4 and 1 M HC1 owing to the selective reduction of Fe203 components in the films. Sputter-deposited Fe-Ti alloy films containing more than 39 at.% Ti passivated anodically in 1 M H2SO4 and 1 M HCI, and showed high con:osion resistance. The FezO3-TiO2 artificial passive films have a higher corrosion resistance than real passive films on the sputter-deposited Fe-Ti alloy films in 5 M HC1.