回火温度对Cu-Cr-Ti马氏体耐磨钢组织及强韧性的影响  

Effect of tempering temperature on microstructure and mechanical properties of Cu-Cr-Ti martensite wear-resistant steel

作　　者：邓杰 宋新莉[1] 郑爱琴 孙新军[2] 贾涓[1] 梁小凯[2] DENG Jie;SONG Xin-li;ZHENG Ai-qin;SUN Xin-jun;JIA Juan;LIANG Xiao-kai(State Key Laboratory of Refractory Materials and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China;Department of Structural Steels,Central Iron and Steel Research Institute,Beijing 100081,China)

机构地区：[1]武汉科技大学耐火材料与冶金国家重点实验室,湖北武汉430081 [2]钢铁研究总院工程用钢研究所,北京100081

出　　处：《钢铁研究学报》2019年第12期1031-1038,共8页Journal of Iron and Steel Research

基　　金：国家重点研发计划资助项目(2017YFB0305100)子课题(2017YFB0305101)

摘　　要：矿山机械用耐磨钢构件服役环境恶劣而常常出现磨损失效,研究适用于复杂工况下的高耐磨钢成分、工艺与组织性能的关系,有利于提高耐磨构件的服役寿命并降低经济损失。利用SEM、TEM、洛氏硬度计、万能拉伸试验机及冲击试验机等,研究了160~400℃不同回火温度下Cu-Cr-Ti马氏体耐磨钢的组织形貌、强度硬度及-20℃冲击韧性的变化。结果表明,试验钢淬火态组织主要为板条马氏体,当回火温度为160℃时,马氏体板条依然清晰,但随回火温度升高到400℃,马氏体板条界渐渐消失,基体中出现大量片状或粒状渗碳体。EDS分析发现样品钢基体中含有纳米级Ti、Nb的碳氮化物。随回火温度升高,基体组织演变导致强化机制发生变化,回火温度为300℃,综合力学性能最佳,其抗拉强度为1 500 MPa,屈服强度1 100 MPa,伸长率为15.5%。随回火温度升高,-20℃冲击韧性由60 J/cm^2逐渐降低到36.3 J/cm^2。The wear failure often occurs because of the bad service environment of mining machinery components.Studying the relationship between the composition,process,microstructure and properties for high wear-resistant steel under complex conditions is beneficial to improve the service life of wear-resistant components and reduce economic losses.The changes of microstructure,strength,hardness and impact toughness at-20℃for Cu-Cr-Ti martensite wear-resistant steel at tempering temperatures from 160 to 400℃were studied by SEM,TEM,Rockwell hardness tester,universal tensile machine and impact machine.The results show that the lath martensite is obtained and the lath martensite still exists for the steel tempered at 160℃.The martensite lath boundary become indistinct and large amount of flaky or granular cementite appears with the tempering temperature increasing to 400℃.Nano-scale Ti,Nb carbonitrides were found in the steels by EDS analysis.The mechanical properties change with the tempered microstructure and the most excellent mechanical properties is obtained for the steel tempered at 300℃,whose yield strength is 1100 MPa,tensile strength is up to 1500 MPa,and the elongation is 15.5%.As the tempering temperature increases from 160 to 400℃,the impact toughness at-20℃decreases from 60 J/cm^2 to 36.3 J/cm^2 gradually.

关 键 词：马氏体耐磨钢 回火温度 板条马氏体 强化机制 

分 类 号：TG1[金属学及工艺—金属学]