Abstract: The change of morphology and ingredient of inclusions in cold heading steel SWRCH22 A before and after feeding calcium wire in 80 t LF liquid steel has been analyzed and studied by scanning electron microscope, and the thermodynamics calculation for modification of inclusions in steel by calcium treatment is carried out. Research results show that after calcium treatment of liquid steel SWRCH22A the Mn in incdusions is placed by Ca, the inclusion Al₂O₃ in liquid steel in tundish is modified to form low melting point calcium aluminate 12CaO·7Al₂O₃ ； and during calcium treatment of liquid steel the necessary condition to form easily floating up and removing liquid inclusion 12CaO·7Al₂O₃ is [Al]_T²/[Ca]_T³≤10.58×10⁴.

Key words: Cold Heading Steel, LF, Calcium Treatment, Inclusion Modification, Thermodynamics Calculation

摘要： 利用扫描电镜对80 t LF钢液喂钙处理前后的冷镦钢SWRCH22A中夹杂物形态和组成的变化进行了分析和研究,对钙处理钢中夹杂物的变性进行了热力学计算。研究表明,SWRCH22A钢液钙处理后夹杂物中的Mn被Ca置换,中间包内钢中Al₂O₃夹杂变性生成低熔点铝酸钙夹杂12CaO·7Al₂O₃;如要钢液钙处理生成易上浮排除的液态12CaO·7Al₂O₃夹杂的必要条件是[Al]_T²/[Ca]_T³≤10.58×10⁴。

关键词: 冷镦钢, LF, 钙处理, 夹杂物变性, 热力学计算