Journal of Korea Foundry Society (한국주조공학회지)

Korea Foundry Society (한국주조공학회)
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An Assessment on the Formation of Oscillation Mark of the Continuously Casted Steel Slabs

연속주조된 강재 슬래브 표면의 Oscillation Mark 형성에 관한 평가

  • Park, Tae-Ho (Dept. of Materials Science and Metallurgy, Kyungpook National University) ;
  • Kim, Ji-Hun (Center for Noncrystalline Materials, Department of Metallurgical Engineering Yonsei University) ;
  • Choi, Joo (Iron & steel Making Research Team,Technical Research Laboratories, POSCO) ;
  • Ye, Byung-Joon (Dept. of Materials Science and Metallurgy, Kyungpook National University)
  • 박태호 (경북대학교 금속공학과) ;
  • 김지훈 (연세대학교 공과대학 재료공학부 준결정재료연구단) ;
  • 최주 (포스코 기술연구소) ;
  • 예병준 (경북대학교 금속공학과)
  • Published : 2003.10.20
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Abstract

In early solidification during the continuous casting of steel slabs, the formation of oscillation marks on the surface of slabs was mainly affected by carbon contents and casting conditions. The control of oscillation mark is required for the HCR(Hot Charged Rolling) process because the deep oscillation marks seriously deteriorate the surface qualities of steel slabs. The metallographic study has revealed that the oscillation mark can be classified principally according to the presence or absence of a small 'subsurface hook' and the depth of the oscillation marks in the subsurface structure at the basis of individual oscillation marks. The subsurface hook of oscillation marks was either straight or curved. When the amount of overflow was small and the subsurface hook was formed in the top of oscillation marks, the subsurface hook was straight and the oscillation mark was shallow. The oscillation marks without subsurface hook have small early solidification shell and were formed wide. The actual negative strip time$(t_N)$ was changed by the effect of meniscus level fluctuation Therefore irregular early solidification shell and oscillation mark were formed.

Keywords

References

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