关键词: 氮, 316LN奥氏体不锈钢, 拉伸性能, 点腐蚀, 晶间腐蚀

Abstract: The steel 316LN for test (/% : 0.015C, 0. 65Si, 0. 90Mn, 17.3Cr, 12.8Ni, 2. 6Mo, 0. 018 ~ 0. 200N) is melted by a 50 kg vacuum induction furnace, adding chromium nitride in atmosphere after vacuum refining. The ingot is forged to Φ20 mm bar and hot-rolled to 4 mm sheet, then solid-solution-treated respectively at 1 100 for 30 min and 10 min, water quenching. Research results show that with increasing every 0. 010%N in stainless steel 316LN, the steel tensile strength and yield strength increase respectively by 9 MPa and 7 MPa, but the steel elongation decreases by 0. 55% , while the nitrogen content in steel on steel reduction of area has no influence, it keeps to about 72. 5% ; the nitrogen strongly improves the pitting corrosion resistance of stainless steel 316LN, with increasing every 0. 010% N, the pitting breakdown potential increases by 7 mV ； and appropriate adding nitrogen in steel (0. 079% N) is available to improve intergranular corrosion resistance of stainless steel 316LN, but excessive nitrogen content (more than 0. 120% N) is harmful to intergranular corrosion resistance of steel.