控温淬火工艺对Q960E超高强钢板组织性能的影响  

Effect of temperature-controlled quenching process on microstructure and properties of Q960E ultra high strength steel plate

作　　者：张家文 付天亮[1] 吴昊 顾小阳 王昭东[1] ZHANG Jia-wen;FU Tian-liang;WU Hao;GU Xiao-yang;WANG Zhao-dong(State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,China;Nanjing Iron and Steel Co Ltd,Nanjing 210035,China)

机构地区：[1]东北大学轧制技术及连轧自动化国家重点实验室,辽宁沈阳110819 [2]南京钢铁股份有限公司,江苏南京210035

出　　处：《材料热处理学报》2021年第2期89-97,共9页Transactions of Materials and Heat Treatment

摘　　要：研究了控温淬火新工艺对Q960E超高强工程机械用钢板组织性能的影响,测量了其静态CCT曲线,并与常规淬火+回火工艺进行了对比。结果表明:实验钢马氏体临界转变冷速为5℃/s,马氏体相变温度M_(s)、M_(f)分别为401℃、240℃。钢板在超快冷系统中淬火时,通过测温仪精确控制其心部温度达到M_(f)点以下100℃和200℃后停止淬火,钢板表面出现"返温"现象,使钢板发生自回火效应,其组织为回火板条马氏体,与常规淬火+回火组织相似,但综合力学性能更优,自回火效果良好。当终冷温度为100℃时,实验钢的综合性能最佳,屈服强度在1040 MPa以上,抗拉强度约为1350 MPa,伸长率在14%以上,-40℃冲击吸收能量大于74 J。Effect of new temperature-controlled quenching process on microstructure and properties of Q960 E ultra high strength steel plate was studied, its static CCT curves were measured, and compared with the conventional quenching and tempering process. The results show that the critical transformation cooling rate of martensite of the experimental steel is 5 ℃/s, and the martensitic transformation temperature M_(s) and M_(f) is 401 ℃ and 240 ℃, respectively. When the steel plate is quenched in an ultra-fast cooling system, stop quenching by accurately controlling the core temperature to 100 ℃ and 200 ℃ below M_(f) point by the thermometer, and the surface of the steel plate will appear "return temperature" phenomenon, which make the steel plate to have a self-tempering effect. The microstructure of the steel plate after temperature-controlled quenching process is tempered lath martensite due to self-tempering, which is similar to the conventional quenching+tempering microstructure, but the comprehensive mechanical properties are better, and the self-tempering effect is well. When the final cooling temperature is 100 ℃, the comprehensive mechanical properties of the experimental steel are the best, the yield strength is above 1040 MPa, the tensile strength is about 1350 MPa, the elongation is above 14%, and the-40 ℃ impact absorbed energy is more than 74 J.

关 键 词：控温淬火 超高强钢 自回火 组织性能 

分 类 号：TG142.3[一般工业技术—材料科学与工程]