| 摘要 |
PURPOSE:To manufacture an alloy steel material having satisfactory hot workability and hindering effectively the adsorption of a high purity fluid by properly cold working an austenitic steel contg. a restricted amt. of B and by heat treating the cold worked steel at a specified temp. in gaseous N2 or NH3. CONSTITUTION:An austenitic steel or the like contg. 0.001-0.1wt% B is cold worked at 5-60% working rate by drawing, rolling or other method. Only the surface of the steel may be cold worked by shot peening or other method. The cold worked steel is heat treated at 650-950 deg.C in gaseous N2 or NH3. By this heat treatment, BN is deposited on the surface of the steel in a short time without deteriorating the hot workability. When the resulting alloy steel material of an austenitic stainless steel or the like comes in contact with a high purity fluid, it can effectively hinder the adsorption of the fluid itself or impurities in the fluid. |
