U71Mn重轨钢轧制后夹杂物分布行为研究  

Study on the inclusion distribution behavior of U71Mn heavy rail steel after rolling

作　　者：宋光洁 王奕 何建中[2] 张达先 付建勋 Song Guangjie;Wang Yi;He Jianzhong;Zhang Daxian;Fu Jianxun(Center for Advanced Solidification Technology,School of Materials Science and Engineering,Shanghai University,State Key Laboratory of Advanced Special Steel,Shanghai 200444,China;Inner Mongolia Baogang Steel Union Co.,Ltd.,Baotou 014010,Inner Mongolia,China)

机构地区：[1]上海大学材料科学与工程学院先进凝固技术中心,省部共建高品质特殊钢冶金与制备国家重点实验室,上海200444 [2]内蒙古包钢钢联股份有限公司,内蒙古包头014010

出　　处：《钢铁钒钛》2024年第6期159-166,共8页Iron Steel Vanadium Titanium

基　　金：中央引导地方科技发展资金(Nos.2022ZY0124)。

摘　　要：非金属夹杂物的形态和分布对重轨钢的性能具有显著影响。采用光学显微镜、扫描电镜、夹杂物三维刻蚀仪、Thermo-calc软件对某厂生产的U71Mn重轨钢中的夹杂物进行了研究。结果表明,U71Mn重轨钢中轨腰处夹杂物的平均等效直径、长宽比最大,数量密度最小。轨头、轨腰、轨底的夹杂物密度分别为18、12、14个/mm^(2),平均等效直径分别为2.5、2.7、2.4μm,平均长宽比分别为7.4、13.3、6.4。钢中夹杂物以单独存在的MnS和CaO·Al_(2)O_(3)·SiO_(2)·MgO复合夹杂物为主。轨头和轨底处的MnS尺寸较小,集中分布在10~50μm;轨腰处的MnS夹杂物尺寸较大,多在20~80μm,且存在多条大尺寸的MnS被轧制在同一条水平线上。CaO·Al_(2)O_(3)·SiO_(2)·MgO复合夹杂物沿轧制方向普遍呈近球形和不规则形。The morphology and distribution of non-metallic inclusions significantly affect the performance of heavy rail steels.This study employed optical microscopy,scanning electron microscopy,a three-dimensional etching instrument for inclusions,and Thermo-calc software to investigate the inclusions in U71Mn heavy rail steel produced by a certain factory.The results show that the average equivalent diameter and aspect ratio of inclusions at the waist of the U71Mn heavy rail steel are the largest,while the number density is the smallest.The inclusion densities in the rail head,waist,and base are 18,12,and 14/mm^(2),respectively,with the average equivalent diameters of 2.5,2.7,and 2.4μm,and the average aspect ratios of 7.4,13.3,and 6.4,respectively.The main inclusions in the steel are individual MnS and complex inclusions of CaO·Al_(2)O_(3)·SiO_(2)·MgO.The sizes of MnS at the rail head and base are relatively small,mainly distributed between 10~50μm.The sizes of MnS inclusions at the rail waist are larger,mostly between 20~80μm,with several large-sized MnS rolled on the same horizontal line.The complex inclusions of CaO·Al_(2)O_(3)·SiO_(2)·MgO generally appear near-spherical or irregular along the rolling direction.

关 键 词：U71Mn重轨钢 夹杂物 轧制变形 热力学分析 

分 类 号：TF76[冶金工程—钢铁冶金] TG115.2[金属学及工艺—物理冶金]