形变热处理对低碳Co-Cr-Mo-Ni合金钢组织性能的影响  

Microstructure and mechanical properties of a low-carbon Co-Cr- Mo-Ni steel processed by thermo-mechanical treatment

作　　者：杨彬 王迎春[1,2] 迟宏宵 周健[3] 熊志平[1,2] 程兴旺 YANG Bin;WANG Yingchun;CHI Hongxiao;ZHOU Jian;XIONG Zhiping;CHENG Xingwang(School of Materials Science and Engineering,Beijing Institute of Technology,Beijing 100081,China;National Key Laboratory of Science and Technology on Materials under Shock and Impact,Beijing 100081,China;Research Institute of Special Steels,Central Iron and Steel Research Institute Co.,Ltd.,Beijing 100081,China;Tangshan Research Institute,Beijing Institute of Technology,Tangshan063003,Hebei,China)

机构地区：[1]北京理工大学材料学院,北京100081 [2]冲击环境材料技术国家级重点实验室,北京100081 [3]钢铁研究总院有限公司特殊钢研究院,北京100081 [4]北京理工大学唐山研究院,河北唐山063003

出　　处：《钢铁研究学报》2024年第3期389-395,共7页Journal of Iron and Steel Research

基　　金：国家科技重大专项资助项目(J2019-VI-0019-0134)。

摘　　要：为了提高低碳高合金钢的强度,开展形变热处理变形量对其组织演变和力学性能影响研究。结果表明,试验钢经过变形量为20%~60%的形变淬火、深冷以及高温回火后的组织由回火马氏体、残余奥氏体和碳化物组成;与常规淬火回火试样相比,经变形量为20%的形变热处理后,由于回火马氏体板条较粗,残余奥氏体体积分数较高,导致强度降低,塑性增加;随着形变热处理的变形量逐渐增加,位错密度增加,回火马氏体板条细化,残余奥氏体体积分数减少,强度逐渐增加,塑性下降。当变形量为60%时,试验钢的屈服强度达到1 547 MPa,较未形变试样提升了约13%,同时抗拉强度达到1 810 MPa,伸长率为17%,获得了高强度和良好的强塑性匹配。In order to improve the strength of low-carbon high-alloy steels, the influence of deformation of thermo-mechanical treatment on microstructure evolution and mechanical properties was studied. The results show that the microstructures of the steel after processing by thermo-mechanical treatment with deformation in the range of 20%-60%, cryogenic treatment and tempering contain the complex phases with tempered martensite, retained austenite and a few carbides. Compared with the conventional quenching and tempering sample, the strength of steel decreases with the elongation increase due to the thicker tempered martensite and a higher fraction of retained austenite after the thermo-mechanical treatment with the deformation of 20%. With deformation increasing from 20% to 60%, the dislocation density increases, the width of tempered martensite lath and the fraction of retained austenite decreases simultaneously, which leads to an improvement in the strength and a decrease in ductility. When the deformation reaches to 60%, the yield strength is higher by about 13% than that of the un-deformed quenching-tempering specimen, and the yield strength, ultimate tensile strength and elongation of the steel are 1 547 MPa, 1 810 MPa and 17%, respectively, achieving a good strength-ductility matching.

关 键 词：低碳高合金钢 形变热处理 回火马氏体 残余奥氏体 力学性能 

分 类 号：TG142.1[一般工业技术—材料科学与工程]