Effect of Steel Making Slag on Castability of Medium Carbon Re-Sulfur Steel Grades

Abstract:

Abstract. One of the everlasting problems existing in alloy steel plant is clogging of Submerged Entry Nozzle(SEN) due to accumulation of De-oxidized/Re-oxidized products while casting Medium Carbon Re-Sulfur Steel grades(forging grades).After complete De-sulphurization and De-oxidation, liquid steel have been subjected to Ca-treatment which promote deep De-oxidation and deep De-sulphurization in addition to inclusion morphology control. Finally liquid steel have been injected with sulfur cored wire for chemistry requirement of 0.02-0.035%. All these conditions encourage thermodynamically favorable conditions for formation of various combination of oxide and sulphide inclusions which are highly detrimental to castability in continuous casting of integrated steel mill. This becomes one of the major process interruptions which directly terminate production capacity day by day and also affects the quality of cast product. As well said before “Best Slag Maker Is Best Steel Maker”, we mainly focused on secondary steel making slag at different stages, and found the relation of castability with respect to slag behavior. We arrived at optimal slag nature for better castability in continuous casting of steel.

• Periodical: Advanced Materials Research (Volume 585)
• Pages: 364-368
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.585.364
• Online since: November 2012
• Authors: K. Ashok, J. Venkatesan, P.G. Venkatakrishnan
• Keywords: Ca Treatment, Inclusion, Re-Oxidation, Submerged Entry Nozzle

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