Cleaning IF molten steel with dispersed in-situ heterophases induced by the composite sphere explosive reaction in RH ladles

Abstract

A novel fine inclusion removal technology was put forward with dispersed in-situ heterophases induced by the composite sphere explosive reaction. A composite sphere with this function was designed and prepared using a laboratory scale batch-type balling disc (at 12 r/min), and the composite sphere was fed at the end of the RH refining process. The results indicate that inclusions in the IF molten steel can be removed effectively by feeding composite spheres in RH ladle. Compared with conventional inclusion removal technology, using this novel technology, the amount of oxide inclusions can be decreased to a lower level and the inclusion size becomes finer, the total oxygen content in the as-cast slab can approach 5×10⁻⁶, and the cost per ton of steel produced can be reduced by 5–12 Yuan RMB.

Keywords

IF steel / refining / bubbles / slags / filtration / inclusions

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