含钛焊丝钢小方坯连铸水口的结瘤机制

 利用扫描电镜对含钛焊丝钢中夹杂物性质及连铸水口结瘤物的物相组成进行了分析，并结合热力学计算研究了水口结瘤的形成机制。结果表明，LF 精炼出站钢液中存在大量Al2O3、TiO2夹杂物，并不断附着沉积在水口内壁形成氧化铝型、氧化钛型或两者结合的结瘤物，连浇炉数仅为4次。通过优化钢中［Al］-［Ti］-［O］关系，控制铝质量分数在钛-铝竞争氧化平衡线之上，即w(［Ti］)/w(［Al］)4/3>84.49 且w(［Ti］)/w(［Al］)>7.46，当钢液中w(［Al］)<0.0068%时，能够降低Al2O3夹杂比例，有效减轻水口结瘤，连浇炉数提升至6炉次。

Clogging Mechanism of Nozzles for Billet Continuous Casting of Welding Wire Steel Containing Titanium

The properties of inclusions in the welding wire steel and phases of caster nozzles were investigated by SEM, and the forming mechanism of the nozzle clogging was also studied by thermodynamic calculation. The results shows that large amounts of Al2O3 and TiO2 inclusions exist in the molten steel at the end of LF refining, and precipitates on the inner nozzles to form the clogging of alumina type, titania type, and two both individually, the continuous heats are merely 4. By optimizing the relationship of ［Al］-［Ti］-［O］ to make the content of w(［Al］) above the equilibrium line between Al-Ti, w(［Ti］)/w(［Al］)4/3>84.49, and w(［Ti］)/w(［Al］)>7.46, when w(［Al］) less than 0.0068%, the Al2O3 inclusions decrease obviously, the nozzle clogging can be efficiently reduced, and the continuous casting heats increase to 6.