Corrosion behavior of pre-oxidized and thermally nitrided stainless steel for polymer electrolyte membrane fuel cell bipolar plates

Thermal nitridation with pre-oxidation of 430 stainless steel was performed in order to improve both the corrosion resistance and the electrical conductivity. As shown by SEM, EDS and AES exhibit ordered mixed Fe/Cr-oxide and Cr-nitride structure. The corrosion resistance of SS430 was enhanced by the oxide formed by the pre-oxidation, especially under anodic condition, and the Cr-nitride formed by substrate serves to improve electrical conductivity in the simulated PEMFC environment.

► Four hundred and thirty stainless steel (<20 wt.% Cr) was used as sample.
► The effect of surface modified stainless steel by pre-oxidation and thermal nitridation.
► The performance of surface modified stainless steel in simulated environments of PEMFCs.
► The enhancement of corrosion resistance and electrical conductivity of stainless steel.