The comparison of the corrosion resistance of advanced ferromagnetic stainless steels by Mott-Schottky approach

摘要

Ferromagnetic stainless steels (SSs) have been investigated as potential candidates for dental prosthesis applications in replacement of magnetic attachments made of noble and expensive alloys. In order to be used as biomaterials, their corrosion resistance has to be appropriate. The corrosion resistance of passive materials is related to the characteristics of the passive film formed and their properties might be investigated by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curves, and Mott- Schottky approach. The corrosion resistance and the capacitance of the passive films formed on PM2000, DIN 1.4575, and 17-4 PH advanced SSs during 2 days of immersion in a phosphate buffered saline solution (PBS), at 25℃ and pH 7.0 were studied by electrochemical techniques. A commercial alloy Dyna EFM was also analyzed for comparison reasons. The results showed that films on tested materials behave as both n-type and p-type semiconductors and the PM2000 presented the highest corrosion resistance among all of them.