Passivation potential regulating corrosion resistance and antibacterial property of 316L-Cu stainless steel in different simulated body fluids

ABSTRACT

In this work, the corrosion resistance of 316 L-Cu stainless steel (SS) after passivation at different potentials was studied by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The antibacterial property of passivated 316 L-Cu SS was also investigated by plate counting and live-dead cell staining combined with scanning electron microscope (SEM) observation. X-ray photoelectron spectroscope (XPS) was performed to analyse the composition of passive film. The results showed that the corrosion resistance increased with increase of the passivation potential from 600 mV to 750 mV, due to the enhancement of Cr₂O₃ and Cu(OH)₂ contents in passive film. When the passivation potential was increased to 900 mV, Cr(OH)₃ in passive film gradually dissolved and transformed to CrO₄^2–, decreasing the stability of passive film. The higher compactness of passive film indicated a declined antibacterial performance.

KEYWORDS:

• Cu-bearing stainless steel
• passive film
• corrosion resistance
• antibacterial property

Disclosure statement

The authors declare that they have not known the competing financial interests or personal relationships that could have appeared to influence the work reported in this article.

Additional information

Funding

This work was financially supported by the National Key Research and Development Program of China [grant number 2016YFB0300205], the National Natural Science Foundation of China [grant number 51501199], the State Key Program of National Natural Science of China [grant number 51631009], and Foshan Science and Technology Program [grant number 2017AG100041].