Mould flux for continuously casting steel - to absorb alumina inclusions and provide controlled viscosity

摘要

Flux contains by wt. 30-65% glass, up to 60% cement clinker, up to 60% limestone up to 10% fluorspar, up to 25%. sodium carbonate, and 1-5% carbon. The CaO:SiO2 ratio is 0.6-1.4, maximum S content 0.2%, maximum Fe2O3 0.5%, maximum Co2 30%, maximum H2O 0.7%, maximum B2O3 5% and maximum Al2O3 8%, while the slag formed by melting of the flux must have a viscosity of 0.5-10 poise at 1300 degrees C and 50 poise at 1200 degrees C. Pref. the glass is lead-free, and the flux is a powder 90% of which is 75 mu and 100% of 250 mu. The flux is added to the mould when continuously casting steel. The components are cheap, readily available, and can be readily ground.