摘要
在传统轴承钢GCr15的基础上,添加合金元素Si、Mo以及微合金元素V得到一种新型微合金化轴承钢,并优化传统马氏体轴承钢的热处理工艺,将新型微合金化轴承钢在M_(s)(马氏体开始形成的温度)点以下进行等温处理,得到等温马氏体组织。采用扫描电镜(SEM)、X射线衍射(XRD)、洛氏硬度计、冲击实验和拉伸实验等研究了不同热处理工艺对微合金化等温马氏体轴承钢微观组织和力学性能的影响。结果表明:实验钢在M_(s)以下等温后组织主要由马氏体(M)、残留奥氏体(RA)以及未溶碳化物组成,当等温时间延长至60 min时,组织中出现了少量针状贝氏体。经不同工艺热处理后实验钢的硬度均在61 HRC以上。实验钢在170℃等温淬火后,冲击韧性相对较高,原因是组织中有较多的残留奥氏体,但较高的残留奥氏体含量降低了其抗拉强度。在170℃等温淬火15 min后,实验钢的综合性能较好,其硬度、冲击韧性和抗拉强度分别为62.4 HRC、52 J/cm^(2)和2139 MPa。
On the basis of traditional bearing steel GCr15,a new type of microalloyed bearing steel was obtained by adding alloying elements Si,Mo and microalloying element V.The heat treatment process of the traditional martensite bearing steel was optimized,and the new-type microalloyed bearing steel was isothermally treated below M_(s)point(the temperature at which martensite begins to form)to obtain isothermal martensite structure.The effects of different heat treatment processes on microstructure and mechanical properties of the microalloyed isothermal martensite bearing steel were studied by means of scanning electron microscopy(SEM),X-ray diffraction(XRD),Rockwell hardness tester,impact test and tensile test.The results show that the microstructure of the experimental steel after isothermal treatment below M_(s)is mainly composed of martensite(M),retained austenite(RA)and undissolved carbide.When the isothermal time is extended to 60 min,a small amount of acicular bainite appears in the microstructure.The hardness of the experimental steel after different heat treatments is above 61 HRC.After isothermal quenching at 170℃,the impact toughness of the experimental steel is relatively high because there is more retained austenite in the microstructure,but the higher retained austenite content reduces the tensile strength.The comprehensive properties of the experimental steel after isothermal quenching at 170℃for 15 min are good,with hardness,impact toughness and tensile strength of 62.4 HRC,52 J/cm^(2)and 2139 MPa,respectively.
作者
王艳辉
李雪峰
刘柏松
徐东
姚菲
曾洪涛
赵雷杰
武东东
李丽
WANG Yan-hui;LI Xue-feng;LIU Bai-song;XU Dong;YAO Fei;ZENG Hong-tao;ZHAO Lei-jie;WU Dong-dong;LI Li(Key Laboratory of Intelligent Industrial Equipment Technology of Hebei Province,Hebei University of Engineering,Handan 056038,China;Technology Innovation Center for High Quality Cold Heading Steel of Hebei Province,Hebei University of Engineering,Handan 056038,China;Whole Processes of High Quality Fastener Application Technology Research Center of Universities in Hebei Province,Hebei Taihang Iron and Steel Group Co Ltd,Handan 056305,China;Handan Iron&Steel Group Co Ltd,Handan 056001,China)
出处
《材料热处理学报》
CAS
CSCD
北大核心
2023年第11期176-183,191,共9页
Transactions of Materials and Heat Treatment
基金
国家自然科学基金(52001105,U20A20272)
河北省自然科学基金资助(E2022402107,E2020402101)
河北省高等学校科学技术研究项目资助(BJ2021012,CXY2023004)。
关键词
轴承钢
微合金化
等温马氏体
微观组织
力学性能
bearing steel
microalloying
isothermal martensite
microstructure
mechanical property
