热处理对超高强度20Mn2Cr汽车钢组织和性能的影响  

Effect of heat treatment on microstructure and mechanical properties of ultra-high strength 20Mn2Cr automobile steel

作　　者：陈健 黄飞[1] 丁汉林 朱国辉[1] 陈其伟[1] 程广萍[1] 王子健 CHEN Jian;HUANG Fei;DING Han-lin;ZHU Guo-hui;CHEN Qi-wei;CHENG Guang-ping;WANG Zi-jian(School of Material Science and Engineering,Anhui University of Technology,Ma’anshan 243002,China;School of Iron and Steel,Soochow University,Suzhou 215006,China)

机构地区：[1]安徽工业大学材料科学与工程学院,安徽马鞍山243002 [2]苏州大学沙钢钢铁学院,江苏苏州215006

出　　处：《材料热处理学报》2021年第7期89-97,共9页Transactions of Materials and Heat Treatment

基　　金：安徽省科技重大专项(18030901085)。

摘　　要：研究了热处理工艺参数对20Mn2Cr钢显微组织和性能的影响规律,并采用扫描电镜、透射电镜、电子背散射衍射技术等研究了不同奥氏体化温度和回火温度下实验钢中的马氏体组织特征和碳化物析出形貌。结果表明,实验钢经900℃奥氏体化处理时可以保证较小的原奥氏体晶粒尺寸及细小的马氏体板条束宽度;550℃再结晶退火可以进一步细化原奥氏体晶粒尺寸及马氏体板条束宽度;淬火后的回火处理有利于Cr碳化物粒子的析出。通过调整热处理工艺,20Mn2Cr钢可以获得1000-1700 MPa级的系列超高强度,同时可以实现超高强度与高塑性的良好匹配。The influence of heat treatment process parameters on microstructure and properties of 20 Mn2 Cr steel was studied, and the effects of austenitizing temperatures and tempering temperatures on martensite structure characteristics and carbide precipitation of the experimental steel were studied by means of scanning electron microscopy(SEM), transmission electron microscopy(TEM) and electron backscattered diffraction(EBSD) technique. The results show that after austenitizing at 900 ℃, the prior austenite grain size and martensite lath width of the experimental steel are small, and the recrystallization annealing at 550 ℃ can further refine the prior austenite grain size and martensite lath width. The tempering treatment after quenching is beneficial to the precipitation of Cr carbide particles. The ultra-high strength of 1000-1700 MPa grade of the 20 Mn2 Cr steel can be obtained by adjusting the heat treatment process, and the good match between the ultra-high strength and the high plasticity can be realized at the same time.

关 键 词：20Mn2Cr钢 热处理 超高强度 高塑性 

分 类 号：TG142.3[一般工业技术—材料科学与工程]