氮含量对高氮不锈钢硬化和软化特性的影响

Effect of nitrogen contentration on hardening and softening properties of high nitrogen stainless steel

为了研究高氮奥氏体不锈钢的加工硬化和退火软化的现象,设计并冶炼了氮质量分数为0.02%~1.20%的无镍奥氏体不锈钢,通过力学性能测试、SEM、EBSD等显微组织观察,分析氮含量对加工硬化和退火软化影响机理。结果表明,氮元素的添加大幅提升了加工硬化速率,氮质量分数从0增加到1.2%,加工硬化率提高了7.06MPa/%。氮能够促进再结晶形核,有效细化晶粒尺寸,氮质量分数为0.4%~1.2%时晶粒细化达60%,但会阻碍晶粒动态回复。

High-nitrogen nickel-free austenitic stainless steels with different mass percent of nitrogen from 0.02% to 1.20% were designed and melted.The effect of nitrogen on work hardening and annealing softening were investigated through mechanical properties test and microstructure examination.The results show that nitrogen enhances the rate of work hardening.The work hardening rate increased 7.06 MPa/% when the mass percent of nitrogen raise from 0 to 1.2%.Nitrogen can promote recrystallization nucleation,refine grain size effectively.The grain refined 60% with mass percent of nitrogen adds from 0.4% to 1.2%,but it can diversify grain orientation.