回火温度对易焊接80 kg级高强钢组织和力学性能的影响  

Effects of Tempering Temperature on Microstructure and Mechaical Properties of 80 kg Grade High Strength Steel for Easy Welding

作　　者：刘丹[1] 陈杰[2] 靳东 张青学[1] LIU Dan;CHEN Jie;JIN Dong;ZHANG Qingxue(Hu'nan Valin Xiangtan Iron&Steel Co.,Ltd.,Xiangtan 411101,China;School of Materials Science and Engineering,Central South University,Changsha 410083,China)

机构地区：[1]湖南华菱湘潭钢铁有限公司,湖南湘潭411101 [2]中南大学材料科学与工程学院,湖南长沙410083

出　　处：《热加工工艺》2024年第10期124-129,共6页Hot Working Technology

基　　金：湖南省省级科技计划项目(2018XK2301)。

摘　　要：研究了不同回火温度对80 kg级直接淬火钢组织和性能的影响。结果表明:直接淬火钢具有较高的强韧性组合和高温回火抗性,当回火温度在450~650℃时,试验钢仍然保持板条状马氏体的形状和位向,随着回火温度升高,板条发生粗化,伴随着残余奥氏体的分解和碳化物的析出和长大等过程。当回火温度为700℃时,试验钢发生较高程度的再结晶,性能明显恶化。当回火温度为650℃时,试验钢具有最佳的综合力学性能,屈服强度为795 MPa,抗拉强度为821 MPa,断后伸长率为20.6%,标准试样-20℃冲击功为195 J。Effects of different tempering temperatures on the microstructure and properties of 80 kg direct quenched steel were studied.The results show that the direct quenched steel has high strength and toughness combination and high temperature tempering resistance.When the tempering temperature is 450-650℃,the test steel still maintains the shape and orientation of the lath martensite.With the increase of tempering temperature,the slab coarsening occurs,accompanied by the decomposition of retained austenite and the precipitation and growth of carbide.At the tempering temperature of 700℃,a high degree of recrystallization occurs in the test steel,and the properties deteriorate obviously.When the tempering temperature is 650℃,the test steel has the best comprehensive mechanical properties,the yield strength is 795 MPa,the tensile strength is 821 MPa,the elongation after break is 20.6%,and the impact work of the standard sample at-20℃is 195 J.

关 键 词：高强钢 回火温度 显微组织 力学性能 易焊接 

分 类 号：TG156.5[金属学及工艺—热处理]