配分工艺对301奥氏体不锈钢组织和力学性能的影响

Effect of partitioning process on microstructure and mechanical properties of 301 austenitic stainless steel

拟以淬火-配分的新型热处理工艺替代冷变形加工硬化工艺,进而提高亚稳态奥氏体不锈钢的力学性能。以301不锈钢为研究对象,采用光学显微镜、扫描电镜、X射线衍射仪、铁素体测量仪、万能试验机及显微硬度计等表征手段,分析了不同配分热处理制度对301不锈钢微观组织及力学性能的影响。结果表明:301亚稳态奥氏体不锈钢经不同淬火-配分工艺热处理后,其显微组织主要由板条状马氏体、奥氏体以及微量碳化物组成;其力学性能对配分温度不够敏感,但随配分时间的延长会不断优化。在450℃配分30 min后,301奥氏体不锈钢的综合力学性能达到最优,其屈服强度、抗拉强度、伸长率及硬度分别为432. 37 MPa、1212 MPa、44. 28%及193. 16 HV0. 2。

A new heat treatment process of quenching and partitioning was proposed to replace the cold deformation hardening process,so as to improve the mechanical properties of metastable austenitic stainless steel. Taking 301 stainless steel as the research object,the effect of partitioning heat treatment processes on its microstructure and mechanical properties was studied by using the metallographic microscope,scanning electron microscope,X-ray diffractometer,ferrite measuring instrument,universal test machine and hardness tester. The results show that the microstructure of the 301 metastable austenitic stainless steel is mainly composed of martensite,austenite and trace carbide after different quenching-partitioning treatments;the mechanical properties are not sensitive enough to the partitioning temperature,but continue to be optimized with the extension of the partitioning time. After partitioning at 450 ℃ for 30 min,the comprehensive mechanical properties of the steel are optimal,and the yield strength,tensile strength,elongation and hardness are 432. 37 MPa,1212 MPa,44. 28% and 193. 16 HV0. 2,respectively.