Corrosion product film formation mechanism of 110H-13Cr casing steel in simulated ultra-high-temperature gas environment for shale oil production

This study investigated the corrosion film formation mechanism of 110H-13Cr at 350 degrees C in the coexistence of four gases, including H2, H2S, CO2 and H2O, by using techniques such as SEM, EDS, XRD and RAMAN, along with thermodynamic calculations. The results indicate that the average corrosion rate of 110H-13Cr is only 0.0573 mm/a. In this environment, the 110H-13Cr steel spontaneously reacts with H2S and H2O. The corrosion products consist of an easily removable outer Fe(1-x) S film and a dense inner Fe-Cr oxide film. The corrosion film for-mation process comprises an interfacial reaction stage and an element diffusion stage.

Automated summary

This study investigated the corrosion film formation mechanism of 110H-13Cr steel at 350 degrees C in the coexistence of H2, H2S, CO2, and H2O gases. The results showed that the corrosion rate of the steel was low, and the corrosion products consisted of an easily removable Fe(1-x)S film and a dense Fe-Cr oxide film inside the steel.