控轧温度对含Nb热轧H型钢组织性能的影响  

Study on influence of controlled rolling temperatures on microstructure and mechanical properties of H-beam containing Nb

作　　者：陈辉[1,2] 夏勐 吴保桥[1,2] 邢军 汪杰[1,2] 黄琦 CHEN Hui;XIA Meng;WU Bao-qiao;XING Jun;WANG Jie;HUANG Qi(Technical Center,Maanshan Iron and Steel Co.,Ltd.,Maanshan 243000,China;Laboratory of Quality Control and Technical Evaluation of Industrial(Wheel,H-beam)Products of Ministry of Industry and Information Technology,Maanshan 243000,China)

机构地区：[1]马鞍山钢铁股份有限公司技术中心,安徽马鞍山243000 [2]工信部工业(车轮、H型钢)产品质量控制和技术评价实验室,安徽马鞍山243000

出　　处：《轧钢》2020年第3期44-47,共4页Steel Rolling

基　　金：国家重点研发计划资助项目(2017YFB0304703)。

摘　　要：通常采用优化孔型的方法使型钢产品变形更加均匀,从而获得理想的显微组织,提升产品性能。但是孔型优化对于变形量分配的调整幅度有限,无法满足多数高品质钢的控轧要求。根据轧制规程设计,H型钢翼缘变形全部集中在万能轧制阶段,为此,研究了在万能轧制段控轧温度对含Nb热轧H型钢组织和性能的影响。结果表明,随着控轧温度的升高,显微组织中铁素体形状由扁平状逐渐变为等轴状,铁素体晶粒平均尺寸先减小后增大且在900℃时晶粒尺寸最小。当控轧温度控制在850~900℃区段,不仅有效提高生产效率,而且其显微组织为细小均匀的等轴状铁素体+少量珠光体,该温度下试验钢的强度指标优于其他轧制温度,低温冲击韧性也明显提高。Generally,the method of pass optimizing is used to make the deformation of the section steel more uniform,so as to obtain the ideal microstructure and improve the product performance.However,the adjustment amount of deformation distribution is limited by pass optimizing,and it cannot meet the control rolling requirements of most high-quality steels.According to the design of the rolling schedules,the flange deformation of the H-beam is concentrated in the universal rolling stage.To this end,the influence of the controlled rolling temperatures on the microstructure and properties of the hot rolled H-beam containing Nb was studied.As the temperature increases,the shape of the ferrite in the microstructure gradually changes from flat to equiaxed.The average size of the ferrite grains decreases first and then increases,and the grain size is the smallest at 900℃.When the controlled rolling temperature is controlled in the range of 850-900℃,it not only effectively improves the production efficiency,but also the microstructure of product is fine and is composed of uniform equiaxed ferrite and a small amount of pearlite.The strength index of tested steel at this temperature is better than other rolling temperatures,and low temperature impact toughness is also significantly improved.

关 键 词：控温轧制 热轧H型钢 组织 力学性能 

分 类 号：TG335[金属学及工艺—金属压力加工] TG142.1[一般工业技术—材料科学与工程]