›› 2016, Vol. 32 ›› Issue (1): 62-65.

• 凝固与浇铸 • 上一篇    下一篇

小方坯内裂纹漏钢形成机理及控制

徐松1,周青峰1,马建超1,金红军2   

  1. 1. 江苏省(沙钢)钢铁研究院
    2. 张家港沙钢集团有限公司润忠炼钢厂
  • 收稿日期:2015-08-25 修回日期:2015-09-16 接受日期:1900-01-01 出版日期:2016-02-05 发布日期:2016-02-29
  • 通讯作者: 徐松 E-mail:xusong7758@126.com

Formation mechanism and control of internal cracking breakout for billets

  1. 1.
    2. Institute of Research of Iron and Steel(IRIS),Shasteel/Jiangsu Province
    3. Institute of Research of Iron and Steel, Jiangsu Province
  • Received:2015-08-25 Revised:2015-09-16 Accepted:1900-01-01 Online:2016-02-05 Published:2016-02-29

摘要: 采用金相显微镜和扫描电镜对螺纹钢典型内裂纹漏钢坯壳的形貌进行了观察分析,探讨了该类型漏钢的特征及演变过程。研究认为,杂质元素特别是硫的晶间偏析对钢的高温强度及裂纹路径的形成有着重要的影响;结晶器内,坯壳生长不均匀导致铸坯表面产生凹陷,对应位置坯壳厚度较薄,并诱发内裂纹形成;出结晶器后,薄弱的内裂纹处承受应力集中,发生裂纹扩展,情况严重时导致漏钢产生。通过降低钢中的S含量、调整合适的浇铸工艺参数后,螺纹钢小方坯内裂纹漏钢发生率由6.32%降低到1.10%。

关键词: 连铸, 小方坯, 漏钢, 晶界偏析, 内裂纹

Abstract: In order to explore the characteristics of the breakout shell and its evolution process for the thread steel, it was investigated by optical microscope and scanning electron microscope analysis. The results indicate that the intergranular segregation especially sulphur plays an important role in the high temperature mechanical property of the steel and the crack propagation path. In the mold, the inhomogeneous growth of shell would cause the occurrence of longitudinal depression and then induce the formation of internal crack. The weak positions of the billet would subject to stress concentration at the exit of mold, cracks tend to propagate and the breakout may happen in severe cases. By controlling the content of sulphur in steel, adjusting the appropriate process parameters, the breakout ratio of the thread steel decreased from 6.32% to 1.10%.

Key words: continuous casting, Billet, steel-leakage, intergranular segregation