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Metallurgical and Materials Transactions B

, Volume 43, Issue 4, pp 830–840 | Cite as

Calcium Modification of Spinel Inclusions in Aluminum-Killed Steel: Reaction Steps

  • Neerav Verma
  • Petrus C. Pistorius
  • Richard J. Fruehan
  • Michael S. Potter
  • Helmut G. Oltmann
  • Eugene B. Pretorius
Article

Abstract

Calcium treatment is a well-established way to modify solid alumina inclusions to liquid or partially liquid calcium aluminates. Spinels (Al2O3·xMgO) can also form in liquid steel after aluminum deoxidation. Like alumina, the spinels can be modified readily to liquid inclusions by a calcium treatment. The modification of spinels was studied by observing the transient evolution of inclusions, in laboratory and industrial heats. Spinel modification involves the preferential reduction of MgO from the spinel, with Mg dissolving in the steel, and it proceeds through transient calcium sulfide formation, just like in the case of alumina inclusions. Because magnesium dissolves in steel after the calcium treatment of spinels, the reoxidation of the melt will produce new spinels.

Keywords

Liquefaction Liquid Steel Magnesium Content Calcium Aluminate Oxide Inclusion 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

Support of this work by the industrial members of the Center for Iron and Steelmaking Research (CISR) is acknowledged gratefully.

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Copyright information

© THE MINERALS, METALS & MATERIALS SOCIETY and ASM INTERNATIONAL 2012

Authors and Affiliations

  • Neerav Verma
    • 1
    • 2
  • Petrus C. Pistorius
    • 1
  • Richard J. Fruehan
    • 1
  • Michael S. Potter
    • 3
  • Helmut G. Oltmann
    • 4
  • Eugene B. Pretorius
    • 5
  1. 1.Department of Materials Science and EngineeringCenter for Iron and Steelmaking Research (CISR), Carnegie Mellon UniversityPittsburghUSA
  2. 2.ExxonMobil Upstream Research CompanyHoustonUSA
  3. 3.RJ Lee GroupMonroevilleUSA
  4. 4.Nucor SteelMount PleasantUSA
  5. 5.Steelmaking TechnologyNucor SteelMount PleasantUSA

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