管线钢冶炼过程夹杂物行为研究

对管线钢从精炼开始到轧材整个生产过程中夹杂物的行为进行了研究。采用金相、化学等各种分析手段，分析了管线钢钢水、连铸坯及热轧卷的洁净度的变化。试验结果表明：现有的生产工艺在稳态浇注时钢水的洁净度满足产品质量要求，LF精炼后钢中夹杂物的含量明显降低。钢水和稳定态铸坯没有发现大于20μm的夹杂物和聚集的夹杂物。非稳态的头坯热轧卷2m长度内氧化铝夹杂超标，主要位于铸坯的内孤表面；头坯热轧卷的夹杂物检测中发现了K2O等成分，表明开浇过程由于拉速变化引起结晶器卷渣。

STUDY ON INCLUSION BEHAVIORS DURING SMELTING PROCESS OF PIPELINE STEEL

In order to study the inclusion behaviors of pipeline steel from refining process to hot rolled strip, purity degree of steel, slab and hot strip were investigated by the methods of electron microscopy, chemical analysis and SEM. The results showed that, under a steady-state condition, purity degree of steel can meet the requirement of product quality, and after LF refining inclusion amount in steel decreased obviously. Inclusions of which size was more than 20μm were not being found in steel and slab under a steady-state condition. But, for the unsteady-state conditon, the amount of inclusion Al2O3 exceeded the normal level in 2m length along hot strip, and the inclusions alawys existed at the inner surface of slab. In additon, for the inclusions in the hot strip, the chemical composition such as K2O was being found, which indicated that the crystallizer slag entrapment happened because of the change of casting speed at the beginning of casting.