炼钢

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镀锌板表面起皮缺陷原因分析与控制

  

  1. (河北钢铁集团邯钢公司 1.邯宝炼钢厂,河北 邯郸 056015;2.三炼钢厂,河北 邯郸 056015)
  • 接受日期:1900-01-01 出版日期:2015-08-05

Analysis and control of galvanized sheet surface shell defect

  • Accepted:1900-01-01 Online:2015-08-05

摘要: 利用扫描电镜和能谱仪,对超低碳镀锌板表面起皮缺陷进行检测分析,结果发现起皮缺陷与基体明显分层,且分层处嵌有大量的Al2O3夹杂,Al2O3夹杂尺寸5~100 μm。查找该缺陷对应铸坯的浇铸过程发现,对应铸坯浇铸过程SEN水口堵塞、塞棒上涨。结合前期对SEN水口堵塞物的综合分析得知,SEN水口堵塞主要是由于脱氧产生的Al2O3夹杂引起。针对脱氧产生的Al2O3夹杂,通过工艺优化,改善钢包顶渣改质效果,提高渣中w(CaO)/w(Al2O3)至2.3,RH脱碳终点氧质量分数由367×10-6降低至315×10-6,实现超低碳镀锌板表面起皮缺陷的有效控制,缺陷发生率由0.10 %降低至0.01 %以下。

关键词: 表面缺陷, 夹杂物, 水口堵塞

Abstract: Shell defects of ultralow carbon galvanized sheet surface were detected and analyzed using SEM.The results showed that the large particles flawed Al2O3 inclusions were discovered between the surface shell and the substrate distinct layers,and the size of Al2O3 inclusions were 5-100 μm.Looked up the slab casting process of the defect coil,the SEN nozzle clogging was found and the stopper rised.Combined with a comprehensive analysis of the clogging substance of SEN,the clogging substance was caused of Al2O3 inclusions.Through process optimizing,improving the ladle slag effect to increase the w(CaO)/w(Al2O3) to 2.3, and reducing the steel oxygen at the end of RH decarburization from 367×10-6 to 315×10-6,the surface shell defects rate of ultralow carbon galvanized sheet was reduced from 0.10 % to 0.01 %,and controlled effectively.

Key words: surface defect, inclusion, nozzle clogging