Method for forming Cr2O3 film on stainless steel surface

摘要

A method for forming a chromium oxide film on the surface of a stainless steel sample. The method includes: (a) placing a sample having stainless a steel surface into a vacuum furnace, evacuating the vacuum furnace to a pressure of 2×10^−7 to 3×10^−7 Torr, and heating the vacuum furnace to 450 to 600° C. at a rate of 5 to 10° C./min; (b) maintaining the vacuum furnace for 10 to 20 minutes at a temperature of 450 to 600° C. to remove foreign materials from the surface of the stainless steel sample and to extract chromium atoms from the stainless steel substrate; and (c) supplying oxygen to the vacuum furnace while maintaining the temperature until oxygen partial pressure reaches 1×10^−9 to 2.5×10^−7 Torr, so the extracted chromium atoms react with oxygen, producing a chromium oxide (Cr₂O₃) film on the surface of the stainless steel. The dense and smooth Cr₂O₃ film improves oxidation resistance and sorption resistance, and suppresses diffusion and permeation of hydrogen.