时效处理对超高强度20Mn2Cr汽车钢组织性能的影响  

Effect of aging treatment on microstructure and mechanical properties of ultra-high strength 20Mn2Cr automotive steel

作　　者：黄文静 陈健 裘欣[3] 丁汉林 朱国辉 王子健 HUANG Wenjing;CHEN Jian;QIU Xin;DING Hanlin;ZHU Guohui;WANG Zijian(School of Metallurgical Engineering,Anhui University of Technology,Ma'anshan 243002,Anhui,China;No.4 Steelmaking and Rolling General Plant,Maanshan Iron and Steel Co.,Ltd.,Ma'anshan 233241,Anhui,China;School of Optical and Electronic Information,Suzhou City University,Suzhou 215104,Jiangsu,China;School of Iron and Steel,Soochow University,Suzhou 215006,Jiangsu,China)

机构地区：[1]安徽工业大学冶金工程学院,安徽马鞍山243002 [2]马鞍山钢铁股份有限公司第四钢轧总厂,安徽马鞍山233241 [3]苏州城市学院光学与电子信息学院,江苏苏州215104 [4]苏州大学沙钢钢铁学院,江苏苏州215006

出　　处：《钢铁研究学报》2024年第5期627-639,共13页Journal of Iron and Steel Research

基　　金：国家自然科学基金资助项目(52174367)。

摘　　要：研究了时效温度、双级时效处理温度以及碳化物析出对超高强度汽车钢20Mn2Cr冷轧板组织和性能的影响。结果表明,20Mn2Cr钢经过双级时效处理后的硬度远高于单级时效,且在550℃+300℃条件下双级时效时综合力学性能最佳,其抗拉强度、伸长率、强塑积分别为1418.1MPa、10.8%、15.3GPa·%。SEM观察表明,通过双级时效处理可实现20Mn2Cr钢的多相组织设计与调控,550℃+300℃双级时效处理后,20Mn2Cr钢的基体组织为粒状贝氏体及少量马氏体,且存在大量细小的Cr碳化物析出。这种多相组织是导致20Mn2Cr钢强度显著提升并获得强塑性良好匹配的主要原因。The effects of aging temperature,double-step aging treatment and the precipitation behavior of carbides on the microstructure and mechanical properties of ultra-high-strength automotive steel 2oMn2Cr were investigated.The results indicate that the hardness of 20Mn2Cr steel after dual-stage aging treatment is significantly higher than that after single-stage aging.For the double-step aged steel,when the first-step aging temperature is set at 550℃,the optimum comprehensive mechanical properties with tensile strength of 1418.1 MPa,elongation of 10.8%,and product of strength and elongation of 15.3 GPa·%can be obtained.SEM observations show that the double-step aging treatment contributes to the design and control of the multi-phase microstructures of 20Mn2Cr steel.The matrix of the steel after 550 and 300℃double-step aging treatment consists of granular bainite and martensite.A large number of fine Cr-rich carbides can also be found in the double-step aging treated steel.The design of multi-phase microstructures is the primary reason for the enhancement of strength and the achievement of excellent match between strength and plasticity of 20Mn2Cr steel.

关 键 词：20Mn2Cr钢 双级时效 超高强度 碳化物 

分 类 号：TG142.1[一般工业技术—材料科学与工程]