| 摘要 |
PURPOSE: An austenitic stainless steel for gas nitriding and a gas nitriding method of the same are provided to add a small amount of Mo to AISI 304 stainless steel to improve room temperature corrosion resistance. CONSTITUTION: An austenitic stainless steel for gas nitriding contains C of 0-0.08 wt%, Si of 0-1.0 wt%, Mn of 1~ 2 wt%, P of 0-0.045 wt% S of 0-0.03 wt% N of 0-0.1 wt%, Cr of 18~20 wt%, Ni of 8~10 wt%, Mo of 0.1~3.0 wt%, residual Fe, and other inevitable impurities. Mo is 1.5~2.5 wt%. Expanded austenite is formed on the austenitic stainless steel as a nitrided layer. The austenitic stainless steel is nitrided using a nitriding gas in a low temperature region at 300-450 degrees to form S phase on the surface thereof to thereby harden the surface thereof. The nitring gas is ammonia or mixed gas of ammonia and hydrogen. |
