MANUFACTURE OF AUSTENITIC STAINLESS STEEL EXCELLENT IN CORROSION RESISTANCE AND OXIDATION RESISTANCE

摘要

PURPOSE:To improve corrosion resistance and oxidation resistance remarkably, by cold working the surface of a product made of austenitic stainless steel to form body centered cubic structure in the surface layer, then by heating it in a low oxygen atmosphere. CONSTITUTION:A product made of austenitic stainless steel is cooled to a temp. not higher than ordinary temp. and is cold worked, or is cold worked while being cooled with water or with cooling gas to form body centered cubic structure. Then it is heated at a temp. 300-1,200 deg.C in a low-oxygen atmosphere of oxygen partial press. not higher than 10-3 atm. Heating of the stainless steel in an atmosphere of low oxygen partial press. lower than the dissociation oxygen press. of FeO restrains the oxidation of Fe contained in the stainless steel, forming a dense protective coating film which contains Cr2O3 as a main component, and is excellent in corrosion resistance and in oxidation resistance.