Novel concept of cleansing IF molten steel with dispersed in situ phase induced by composite ball explosive reaction in RH ladles

A novel technology for the removal of fine inclusions has been put forward using a dispersed in situ phase induced by an explosive reaction of a composite ball of slag forming materials. A composite ball with this function has been designed and prepared using a laboratory model batch type balling disc (at 12 rev min⁻¹) and the composite ball has been fed at the end of Ruhrstahl–Heraeus refining. The results indicate that feeding composite ball in Ruhrstahl-Heraus ladle is a novel technology and the inclusion in the interstitial free molten steel can be removed effectively. Compared with conventional inclusion removal technology, the number of the oxide inclusions can be decreased to a lower level and the inclusion size becomes finer. Using this novel technology, the total oxygen in the as cast slab can approach to 5 ppm and the steel production cost for per ton can be reduced by 5–12 RMB.