低成本无钒热轧钢筋HRB400E的生产工艺优化  

Production process optimization for low cost vanadium-free hot rolled HRB400E steel bars

作　　者：刘阳 高茗 马莉 胡祯 孙中梅 张士震 Liu Yang;Gao Ming;Ma Li;Hu Zhen;Sun Zhongmei;Zhang Shizhen(Inspection and Certification Co.,Ltd.,MCC,Beijing 100088,China;State Key Laboratory of Advanced Technology for Iron and Steel Metallurgy,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]中冶检测认证有限公司,北京100088 [2]北京科技大学钢铁冶金新技术国家重点实验室,北京100083

出　　处：《金属热处理》2024年第7期294-300,共7页Heat Treatment of Metals

基　　金：国家重点研发计划(2023YFC3807203);中央高校基本科研业务费专项资金(FRF-TP-22-011A1);中国中冶重点研发项目181计划重大研发项目(YCC2022Kt03)。

摘　　要：研究了HRB400E无钒盘螺钢筋的未再结晶区温度和动态CCT曲线,得出了钢筋的工业化生产工艺。结果表明:当应变速率为0.2 s^(-1)时,HRB400E钢在970℃热轧时发生明显的再结晶,当热轧温度降低到850℃及其以下时,HRB400E钢发生部分再结晶或未发生再结晶;当冷却速度小于3℃/s时,HRB400E钢的组织为铁素体和珠光体,冷却速度在5~15℃/s时,得到铁素体、珠光体和贝氏体组织,冷却速度大于15℃/s时,得到珠光体和贝氏体组织。根据试验结果,设置开轧温度为(950±15)℃,进精轧温度为(870±10)℃、吐丝温度为(870±10)℃,1~4号风机开度分别为90%、90%、70%、70%的生产工艺。采用此优化工艺试生产时,钢筋的屈服强度R_(p0.2)≥409.5 MPa,同圈差≤32.6 MPa,最大力总延伸率A_(gt)≥10.26%,微观组织由铁素体和珠光体组成,全流程吨钢成本可降低16元左右。Temperature range of non-recrystallization region and dynamic CCT curves of vanadium-free coil-free snail steel bars HRB400E were studied,and the industrial production process of the steel bars was optimized.The results show that when the strain rate is 0.2 s^(-1),obvious recrystallization occurs in the HRB400E steel when rolling at 970℃,while partially recrystallization or non-recrystallization occur when the rolling temperature is reduced to 850℃and below.The microstructure of the steel is ferrite and pearlite when the cooling rate is less than 3℃/s,ferrite+pearlite+bainite when the cooling rate is in the range of 5-15℃/s,and pearlite+bainite when the cooling rate is over 15℃/s.According to the experiment results,the rolling start temperature,finishing rolling temperature and wire spinning temperature is preset as(950±15)℃,(870±10)℃,and(870±10)℃,respectively,and the opening degree of No.1 to No.4 fans is 90%,90%,70% and 70%,respectively.When this optimized process is used in trial production,the yield strength of the steel bar R_(p0.2)≥409.5 MPa,the difference in the same circle≤32.6 MPa,the maximum total elongation A_(gt)≥10.26%,the microstructure is composed of ferrite and pearlite,and the tonnes steel cost in the whole process is reduced by about 16 Yuan.

关 键 词：未再结晶区 CCT曲线 微观组织 屈服强度 最大力总伸长率 

分 类 号：TF044[冶金工程—冶金物理化学]