冷却温度对热轧双相钢组织和力学性能的影响  

Effect of cooling temperature on microstructure and mechanical properties of a hot-rolled dual-phase steel

作　　者：王成 刘亚军 陈志辉 童善康 甘晓龙[2,3] Wang Cheng;Liu Yajun;Chen Zhihui;Tong Shankang;Gan Xiaolong(Hot Rolling Plant,Wuhan Iron and Steel Co.,Ltd.,Wuhan Hubei 430080,China;State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan Hubei 430081,China;Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,Wuhan University of Science and Technology,Wuhan Hubei 430081,China)

机构地区：[1]武汉钢铁有限公司热轧厂,湖北武汉又430080 [2]武汉科技大学省部共建耐火材料与冶金国家重点实验室,湖北武汉430081 [3]武汉科技大学钢铁冶金及资源利用省部共建教育部重实验室,湖北武汉430081

出　　处：《金属热处理》2025年第1期213-218,共6页Heat Treatment of Metals

基　　金：湖北省教育厅指导性项目(B2022010)。

摘　　要：基于薄板坯连铸连轧工艺条件,通过光学显微镜、万能拉伸机、显微硬度计和X射线衍射仪研究了不同冷却温度对双相钢DP600组织和性能的影响。研究发现,随着冷却温度从640℃升高到720℃,屈服强度和抗拉强度先下降后上升,断裂总延伸率降低。此外,硬度随着冷却温度增加呈先降低后增加趋势,与强度变化趋势相吻合。试验钢在720℃进行冷却后可以获得较高的强度和硬度。铁素体晶粒尺寸随着冷却温度的升高先升高再降低,马氏体体积分数逐渐增加。根据双相钢的强化机理计算表明不同冷却温度下试样的强度差异主要来源于细晶强化、相变强化和位错强化的不同,其中以细晶强化和位错强化为主,强度理论计算结果与试验结果的趋势相吻合。Based on the process of thin slab continuous casting and rolling,the effect of various cooling temperatures after hot rolling on the microstructure and properties of a hot-rolled dual-phase steel was studied by using optical microscope,universal tensile machine,microhardness tester,and X-ray diffractometer.The results show that the yield strength and tensile strength first decrease and then increase,while the total elongation gradually decreases with the cooling temperature increases from 640 ℃ to 720 ℃.In addition,the hardness decreases first and then increases with the increase of cooling temperature,which is consistent with the trend of strength changes,indicating that higher strength and hardness can be obtained after cooling at 720 ℃.The grain size of ferrite first increases and then decreases with the increase of increasing cooling temperature,and the martensite content gradually increases.It is shown from the calculation according to the strengthening mechanism of the dual-phase steel that the difference in strength of the specimens under different cooling temperatures is mainly due to the differences in grain refinement strengthening,transformation strengthening and dislocation strengthening,among which the grain refinement strengthening and dislocation strengthening are the main mechanisms,and the theoretical strength calculation results are in agreement with the experimental results.

关 键 词：双相钢 冷却温度 组织 力学性能 强化机理 

分 类 号：TG142.1[一般工业技术—材料科学与工程]