铝系脱氧剂用量对高级别管线钢洁净度的影响

Effects of Amount of Aluminum Deoxidizer on Cleanness of High Grade Pipeline Steel

板坯生产工艺中多使用铝作为脱氧剂。在理论热力学计算中,铝脱氧剂用量在一定范围内保持钢液中铝和氧之间的动态平衡,超过这个范围,多余的铝生成非金属夹杂物,恶化钢水洁净度,影响钢材性能。文章以L415M钢种为例,通过工业化试验分析研究了转炉工序不同脱氧剂用量夹杂物数量、尺寸的变化,阐明了减少脱氧剂用量对高级别管线钢生产工艺全流程夹杂物的影响。通过提出钢水洁净度控制优化方案,轧材中B类夹杂物小于2级比率从96.8%提高到99.83%。

The aluminum is often used as the deoxidizer in production process of slab. In the theoretical thermodynamic calculation, the amount of aluminum deoxidizer could keep dynamic equilibrium of aluminum and oxygen in liquid steel within limits. If beyond the limit, the surplus aluminum forms non-metallic inclusions so that the cleanness of molten steel is deteriorated and the performances of steel are affected. In the paper, it is analyzed and studied the changes of amount and size for inclusions with different amounts of deoxidizer in converter through industrial tests by taking the L415M steel as an example, elaborated the effects of reducing the amount of deoxidizer on inclusions in the whole production process of high grade pipeline steel. The ratio of inclusions(Class B) less than grade 2 in rolled products is increased from 96.8% to 99.83% by proposing the optimization scheme for controlling the cleanness of molten steel.