Detection and cause analysis of abnormal microstructure of 82B wire rod in prestressed steel strand
PAN Xiaokun1, WANG Haibin2, LI Na2, DI Zengwen2, ZHU Yucheng1, ZHANG Chaolei*1
1. Innovation Research Institute for Carbon Neutrality,University of Science and Technology Beijing,Beijing 100083,China; 2. Xuansteel Company,HBIS Group Co.,Ltd.,Xuanhua 075100,China
Abstract：The abnormal microstructures in 82B wire rod, such as martensite and network cementite, make it easy to fracture during drawing, which seriously affects the economic benefits of production. Martensite grade is closely related to the product quality. Aiming at the problem that 82B wire rod had martensite and even network cementite abnormal structure at the same time, the metallographic structures of the transverse and longitudinal sections of the wire rod were observed by field emission scanning electron microscopy (SEM) and electron probe microanalysis (EPMA). Moreover, the distribution of alloy elements in the cross section was determined to analyze the reasons. Two methods for evaluation of martensite grade were discussed. The results showed that the martensite grade evaluated by the cross-section method was 0.5-1.0 grade higher than that evaluated by the longitudinal cross-section method. The cross-section method should be used in the production batch inspection, while in special cases such as research and handling of user quality objections, the longitudinal cross-section method could be supplemented. The segregation of Mn and Cr elements in the center of 1.01-1.16 was the main reason for the formation of martensite. The main reason for the formation of network cementite was the excessive content of C.
潘晓坤, 王海宾, 李娜, 狄增文, 朱禹承, 张朝磊. 预应力钢绞线82B盘条异常组织检测与成因分析[J]. 冶金分析, 2023, 43(3): 85-90.
PAN Xiaokun, WANG Haibin, LI Na, DI Zengwen, ZHU Yucheng, ZHANG Chaolei. Detection and cause analysis of abnormal microstructure of 82B wire rod in prestressed steel strand. , 2023, 43(3): 85-90.
[1] 金桂香,王福明,付军,等.82B高碳钢盘条中马氏体成因[J].材料热处理学报,2013,34(6):62-68. JIN Guixiang,WANG Fuming,FU Jun,et al.Formation of martensite in 82B high carbon steel wire rod[J].Transactions of Materials and Heat Treatment,2013,34(6):62-68. [2] Dhua S K,Singh C D,Amitava Ray.Metallurgical investigation into the causes of premature failure of high-carbon steel wire rods during hot rolling[J].Journal of Failure Analysis and Prevention,2005,5(4):67-73. [3] 李平,王雷,周青峰.82B中心网状渗碳体产生原因及改善方法[J].钢铁研究学报,2014,26(9):33-36. LI Ping,WANG Lei,ZHOU Qingfeng.Formation reasons and countermeasures of cementite network in the center of 82B wire rods[J].Journal of Iron and Steel Research,2014,26(9):33-36. [4] 刘振成,侯基林,姜德刚.SWRH82B高碳盘条脆断原因分析[J].钢铁,2003,38(4):52-55. LIU Zhencheng,HOU Jilin,JIANG Degang.Analysis of brittle fracture of SWRH82B wire rods[J].Iron and Steel,2003,38(4):52-55. [5] 史杨.B7冷镦钢盘条冷拔断裂原因分析及工艺改进[J].特殊钢,2021,42(2):28-30. SHI Yang.Analysis on cold drawing fracture cause of B7 steel rod coil and process improvement[J].Special Steel,2021,42(2):28-30. [6] 付军,王福明,柴国强,等.82B高碳钢盘条的动态连续冷却组织转变[J].金属热处理,2010,35(8):5-8. FU Jun,WANG Fuming,CHAI Guoqiang,et al.Dynamic continuous cooling transformation of 82B high carbon steel wire rod[J].Heat Treatment of Metals,2010,35(8):5-8. [7] 计云萍,刘宗昌,任惠平,等.高碳钢中马氏体的组织结构及形成机制[J].机械工程材料,2013,37(3):1-4,10. JI Yunping,LIU Zongchang,REN Huiping,et al.Microstructure and formation mechanism of martensite in high-carbon steel[J].Materials for Mechanical Engineering,2013,37(3):1-4,10. [8] 王海宾.SWRH82B钢盘条心部马氏体异常组织分析[J].河北冶金,2015(2):53-55. WANG Haibin.Analysis about unusual structure of martensite in core of SWRH82B steel wire bar[J].Heibei Metallurgy,2015(2):53-55. [9] 孔祥涛,陈兆阳,周德,等.首钢SWRH82B线材异常组织成因分析[J].钢铁,2011,46(10):70-74. KONG Xiangtao,CHEN Zhaoyang,ZHOU De,et al.Genetic analysis for abnormal micro-structure of shougang SWRH82B wire rod[J].Iron and Steel,2011,46(10):70-74. [10] 李冬玲,金呈,马飞超,等.激光诱导击穿光谱原位统计分布分析法测定帘线钢盘条中的元素偏析[J].冶金分析,2014,34(1):1-9. LI Dongling,JIN Cheng,MA Feichao,et al.Original position statistic distribution analysis combined with laser induced breakdown spectrometry for the element segregation in tire cord steel rod[J].Metallurgical Analysis,2014,34(1):1-9. [11] LIN L L,HE W,LI Z L,et al.Causes and control mechanism of abnormal structure in the center of SWRH82B wire-rod-steel[J].Materials Science Forum,2019,944:294-302. [12] 支旭波,张朝晖,杨渭绒.高碳钢盘条SWRH82B心部网状渗碳体产生原因及改善方法[J].山西冶金,2018,41(4):42-44. ZHI Xubo,ZHANG Zhaohui,YANG Weirong.Cause analysis and improvement of network cementite in the core of high carbon wire rod SWRH82B[J].Shanxi Metallurgy,2018,41(4):42-44. [13] Elwazri A M,Yue S,Wanjara P.Effect of prior-austenite grain size and transformation temperature on nodule size of microalloyed hypereutectoid steels[J].Metallurgical & Materials Transactions A,2005,36(9):2297-2305.
