The surface grinding-induced oxide scale exfoliation of an austenitic alloy in supercritical CO2

Abstract

This work studied the effect of surface grinding on the corrosion behaviour of an austenitic stainless steel (SS) in the supercritical CO2. The results show that the polished surface had a typical oxide structure including an outer and an inner oxide layer while the ground surface had a much thinner oxide scale with Cr2O3, SiO2, and Mn2O3 after 3000 h exposure. The C-enrichment lamellar was observed in the oxide scale which was attributed to the exfoliation of the oxide scale and further penetrated into the matrix as Cr-rich carbides in the specimen with a ground surface.