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
杨彬 1王迎春 2迟宏宵 3周健 3熊志平 2程兴旺4
作者信息
- 1. 北京理工大学材料学院,北京 100081
- 2. 北京理工大学材料学院,北京 100081;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. 北京理工大学材料学院,北京 100081;冲击环境材料技术国家级重点实验室,北京 100081;北京理工大学唐山研究院,河北 唐山 063003
- 折叠
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 810MPa,伸长率为 17%,获得了高强度和良好的强塑性匹配.
Abstract
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Key words
low-carbon high-alloy steel/thermo-mechanical treatment/tempered martensite/retained austenite/mechanical property引用本文复制引用
基金项目
国家科技重大专项(J2019-VI-0019-0134)
出版年
2024
NETL
NSTL
万方数据