Prediction of Equiaxed Crystal Ratio in Continuously Cast Steel Slab by Simplified Columnar-to-Equiaxed Transition Model

• Shibata Hiromitsu

  Steel Research Laboratory, JFE Steel Corporation

• Itoyama Seiji

  Steel Research Laboratory, JFE Steel Corporation

• Kishimoto Yasuo

  Steel Research Laboratory, JFE Steel Corporation

• Takeuchi Shuji

  Steel Research Laboratory, JFE Steel Corporation

• Sekiguchi Hiroshi

  East Japan Works (Chiba), JFE Steel Corporation

Abstract

A simplified prediction model of the equiaxed crystal ratio (ECR) in continuously cast slabs of ferritic stainless steel was investigated based on the columnar to equiaxed transition (CET) model proposed by J. D. Hunt. The present model assumes that CET occurs when a parameter G/V^1/2 at a solid fraction of 0.3 is smaller than a critical value, C_ET. This model can explain comparatively well the effects of the casting speed, melt superheat, steel composition, intensity and position of the electromagnetic stirring (EMS), and secondary cooling intensity on measured ECR. The calculated results also show that an optimum EMS position and casting speed for maximizing ECR exist. Moreover, it was found that there is a proportional relationship between the best-fit values of C_ET and N₀^1/3C₀^1/2 calculated from measured data. This means that the simplified Hunt model is applicable to predict ECR in continuously cast slabs. The mechanism by which equiaxed crystal bands are generated is also discussed in relation to the behavior of G/V^1/2.

Journal

• ISIJ International

  ISIJ International 46 (6), 921-930, 2006

  The Iron and Steel Institute of Japan

Keywords

• equiaxed crystal ratio
• continuous casting
• slab
• solidified structure
• prediction model
• columnar to equiaxed transition
• ferritic steel

Details

• CRID: 1390282681463899904
• NII Article ID: 10018047274
• NII Book ID: AA10680712
• DOI: 10.2355/isijinternational.46.921
• COI: 1:CAS:528:DC%2BD28XmtlOltrw%3D
• ISSN: 13475460
• ISSN: 09151559
• Web Site: http://www.jstage.jst.go.jp/article/isijinternational/46/6/46_6_921/_pdf
• Text Lang: en
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed