Nb-V-Ti微合金化低合金钢SG610E 250 mm×2000 mm连铸尾坯封顶工艺试验与实践  

Test and Practice on Capping Process of 250 mm×2000 mm Casting Tail Slab of Nb-V-Ti Microalloying Low Alloy Steel SG610E

作　　者：曹磊 马保振[1] 黄伟青[1] 韩立浩[1] 石永亮[1] Cao Lei;Ma Baozhen;Huang Weiqing;Han Lihao;Shi Yongliang(Material Engineering Department,Hebei College of Industry and Technology,Shijiazhuang 050000)

机构地区：[1]河北工业职业技术学院材料工程系,石家庄050000

出　　处：《特殊钢》2021年第3期31-34,共4页Special Steel

基　　金：河北省自然基金(E2017417008);河北工业职业技术学院科研项目(yzk2020005)资助。

摘　　要：针对低合金钢SG610E 250 mm×2000 mm连铸尾坯封顶工艺进行了试验研究,结果表明,传统的打水封顶工艺,在距离铸坯尾部2000 mm范围内存在严重的中心缩孔,而低拉速无水封顶可以将缩孔尾坯长度减小到了900 mm。但是由于低拉速无水封顶工艺,拉速≤0.2 m/min持续时间长,导致连铸坯表面温度降低,进入第三脆性区,Nb-V-Ti微合金化低合金钢连铸尾坯表面出现了表面横裂纹。为此,开发了一种宽厚板连铸机拉速0.4 m/min不停机无水封顶方法,不仅获得了良好的连铸尾坯内部质量,同时解决了该钢连铸尾坯表面横裂纹的问题。The capping technology of low alloy steel SG610 E 250 mm×2000 mm continuous casting tail slab is studied.The results show that with traditional water-cooling capping process,there are severe shrinkage cavities at distance 2000 mm from the slab end;while with the low-speed casting anhydrous capping,the distance of slab shrinkage cavities decreases to 900 mm,but the slab surface temperature drops into the third brittle zone due to the long duration of≤0.2 m/min casting speed,which lead to transverse cracks on Nb-V-Ti microalloying low alloy steel casting tail slab.Therefore a non-stopped-pouring speed casting 0.4 m/min anhydrous capping technology for wide and thick slab is developed which improves the internal quality and reduces the surface crack incidence of the steel tail slab.

关 键 词：Nb-V-Ti微合金化低合金钢SG610E 连铸尾坯 打水封顶 无水封顶 表面横裂纹 

分 类 号：TF777[冶金工程—钢铁冶金]