大规格SWRS82B钢盘条同圈抗拉强度波动原因分析及改善措施  

Cause analysis and improvement of tensile strength fluctuation in the same circle of large size SWRS82B steel wire rod

作　　者：李月云 王雷 李建华 张宇 Li Yueyun;Wang Lei;Li Jianhua;Zhang Yu(Institute of Research of Iron&Steel(Sha-steel),Suzhou Jiangsu 215625,China)

机构地区：[1]江苏省(沙钢)钢铁研究院,江苏苏州215625

出　　处：《金属热处理》2024年第1期273-278,共6页Heat Treatment of Metals

摘　　要：通过对SWRS82B钢盘条进行同圈抗拉强度、化学成分与显微组织分析,找出了同圈抗拉强度波动大的原因是搭接点处存在异常组织。采用热模拟试验对SWRS82B钢盘条连续冷却过程进行分析,同时检测斯太尔摩冷却情况,找出了异常组织形成原因,结果表明,成分中V元素的加入使得珠光体与贝氏体转变区分离,在冷速≥3℃/s、温度低于550℃时将发生贝氏体转变。由于佳灵装置(是一种安装在斯太尔摩上,用于调节搭接点与非搭接点风量分配的装置)角度设置不合理,搭接点风速较大,过冷奥氏体发生了部分低温转变,相变产物为珠光体+贝氏体,使得同圈抗拉强度波动较大。对佳灵装置与风机风量进行调整,降低了搭接点冷速,将同圈抗拉强度波动由102 MPa降低至49 MPa,抗拉强度合格率由88%提高到100%。Tensile strength,chemical composition and microstructure of SWRS82B steel wire rod in the same circle were analyzed,and the reason for the large fluctuation of stensile trength was found as the presence of abnormal microstructure at the lapping point.The reason for the formation of abnormal microstructure was identified by analyzing the continuous cooling process of the SWRS82B steel wire rod through thermal simulation experiments and detecting the cooling condition of Stelmor.The results show that the addition of V element in the composition causes the separation of pearlite and bainite transformation zones.When the cooling rate is over or equals to 3℃/s and the temperature is below 550℃,the bainite transformation occurs.Due to the unreasonable set of Jialing device(a device which is installed on the Stelmor,and is used to adjust the wind distribution between the lapping point and non⁃lapping point)and the higher wind speed at the lapping point,the supercooled austenite undergoes a partial low⁃temperature transformation,and the phase transformation products are pearlite and bainite,resulting in significant fluctuations of the tensile strength in the same circle.The Jialing device and fan air volume are adjusted to reduce the cooling speed of the lapping point,the tensile strength fluctuation in the same circle is reduced from 102 MPa to within 49 MPa,and the tensile strength qualification rate is increased from 88%to 100%.

关 键 词：SWRS82B钢盘条 抗拉强度波动 热模拟试验 异常组织 佳灵装置 工艺优化 

分 类 号：TG142.1[一般工业技术—材料科学与工程]