Static Corrosion Behavior of 316 Austenitic Stainless Steel at Low-temperature in H₂S-containing Environments

To study the static corrosion mechanism of low-temperature liquid nitrided austenitic stainless steel in H₂S-containing environments, 316 austenitic stainless steel was liquid nitrided at 430℃ for 8 h. The effect of low-temperature liquid nitridation on static corrosion of austenitic stainless steel in H₂S-containing environments was investigated with X ray diffraction analyzer (XRD), scanning electron microscope (SEM), analytical balance, electron probe microanalysis (EPMA) and X ray photoelectron spectroscopy (XPS). The results show that under static corrosion condition, the nitrogen containing supersaturated extended austenite layer (S-phase) formed on the surface of austenitic stainless steel after low-temperature nitridation can effectively prevent the corrosion medium from immersing into the material matrix, which reduces the corrosion weight loss by 34%, and slows down the corrosion degree of the material and significantly improves the surface properties of the material.