Microstructure evolution and mechanical properties of PESR 55Cr17Mo1VN plastic die steel during quenching and tempering treatment  

作　　者：Cong-peng Kang Fu-bin Liu Huai-bei Zheng Hua-bing Li Zhou-hua Jiang Kui Chen Hao-yang Suo Xin-hao Yu 

机构地区：[1]School of Metallurgy,Northeastern University,Shenyang,110819,Liaoning,China [2]State Key Laboratory of Metal Material for Marine Equipment and Application,Anshan,114002,Liaoning,China

出　　处：《Journal of Iron and Steel Research International》2021年第12期1625-1633,共9页

基　　金：This research was sponsored by the National Natural Science Foundation of China(Grant Nos.U1960203,U1908223,and 51774074);Talent Project of Revitalizing Liaoning(Grant No.XLYC1902046);State Key Laboratory of Metal Material for Marine Equipment and Application(Grant No.HG-SKL(2019)13);the"Innovation&Entrepreneurship Talents”Introduction Plan of Jiangsu Province in 2018.

摘　　要：55Cr17Mo1VN high nitrogen martensitic stainless steel is usually applied to the high-quality mold,which is largely produced by the pressurized electro slag remelting process.The microstructure evolution of quenching and tempering heat treatment were investigated and an optimal heat treatment process to achieve excellent mechanical properties was found out.The main precipitates in the steel included carbon-rich type M_(23)C_(6) and nitrogen-rich type M_(2)N.With increasing austenitizing temperature,the equivalent diameter of the precipitates got fined,and retained austenite content increased significantly when the austenitizing temperature exceeded 1020℃.The fracture mode gradually changed from brittle fracture to ductile fracture with increasing tempering temperature from 200 to 550℃.The experimental steel tempered at 350℃ achieved a good combination of hardness(60.6 HRC)and strength(2299.2 MPa)to meet service requirements.Flake M_(23)C_(6) precipitated along martensite lath boundaries and the secondary hardening phenomenon occurred when the tempering temperature was 450℃.Due to the high nitrogen content,M_(2)N precipitated from the inside of laths and matrix when tempered at 550℃.

关 键 词：MICROSTRUCTURE Mechanical property Plastic die steel QUENCHING TEMPERING PRECIPITATE 

分 类 号：TG142.1[一般工业技术—材料科学与工程] TG161[金属学及工艺—金属材料]