连铸工艺对含铌中厚板边裂的影响  

Effect of casting process on Nb plate edge crack

作　　者：鲁献辉[1] 马娥 

机构地区：[1]河北钢铁集团邯钢公司质量检验部,河北邯郸056015 [2]河北钢铁技术研究总院科研管理部,河北石家庄052165

出　　处：《连铸》2015年第4期54-59,共6页Continuous Casting

摘　　要：针对中厚板含铌钢容易出现的边部缺陷问题,对含铌钢边部横裂缺陷进行研究,以解决长期困扰中厚板含铌钢边部质量提升的技术瓶颈。通过铸坯热酸洗检测、钢板金相检测、保护渣岩相分析等手段确定铸坯边裂缺陷来源,对铸坯边裂机理进行归纳分析,通过连铸工艺控制与二冷优化等技术优化,控制钢中酸溶铝质量分数从0.045%下降到0.025%、采用低渣熔点低黏度适宜析晶温度的保护渣、提高铸坯矫直区温度大于900℃等措施,有效改善了铸坯角部传热,较好控制了铸坯角部裂纹的发生,使含铌钢边部横裂得到了有效控制。Easy encountered transverse cracks in Nb steel plate edge were researched to improve the quality. Though hot pickling detection of slab, metallurgical testing of plate, petrographic analysis of mould powder etc., the origin of slab edge crack defect was confirmed. Slab edge crack mechanism was inductively analyzed. By optimizing continuous casting technology which included process control and optimization of secondary cooling, decreasing Als from 0.045% to 0.025%,adopting mould powder with low viscosity and low melting point for suitable crystallization temperature,and increasing slab straightening zone temperature higher than 900 ℃,the slab corner heat transmission was improved, and then the slab corner cracks and Nb steel edge transverse were controlled.

关 键 词：边裂 连铸 二冷优化 保护渣 

分 类 号：TF777[冶金工程—钢铁冶金]