Study on the passive behavior of 304 stainless steel under temperature variation

Abstract

In this paper, the passive behavior of 304 stainless steel (SS) in NaCl solution is studied by electrochemical methods and surface analysis. The polarization measurement results show that the pitting potential (Ep) has a simple linear relationship with the temperature increase. Scanning Kelvin probe results show that the surface potential difference on the surface of 304 SS is well correlated with the temperature. Scanning electron microscope results show that the rupture of the passive film accelerates with the increase of temperature. The X‐ray photoelectron spectroscopy analysis shows that the high temperature causes more oxidation on the surface of 304 SS, leading more Cr3+ oxidized to Cr6+ at high temperature.