Review on Evolution of Oxide Layer and Chromium Depletion Layer of Austenitic Stainless Steel during Industrial Processing

Hot-rolled steel is widely used in the construction, ships, and home appliances due to its excellent mechanical properties and processability. With the rapid development of the manufacturing industry, surface quality has become a key element to measure product quality. Compared with carbon steel, austenitic stainless steel forms a dense Cr₂O₃ film, which endows it with excellent corrosion resistance. As a result, it is widely used in surface engineering applications, where stringent surface quality requirements are often imposed. Oxidation throughout the production process of austenitic stainless steel strips (reheating, hot rolling, coiling, and annealing) is influenced by the interaction of alloy elements and various process parameters. The structure of the oxide layer and the chromium-depleted layer determines the surface quality after pickling. Therefore, the evolutionary pattern of the surface oxidation state during process oxidation is reviewed, which is necessary to improve the surface quality of hot-rolled austenitic stainless steel and the competitiveness of the industry.