Development of low-fluoride and titanium-bearing mould fluxes for medium carbon peritectic steel slab casting

Abstract

High content fluoride added into mould fluxes will cause serious environmental problems, especially corrosion to continuous casters and air pollution. Thus, efforts are focused on reducing the fluorine content in mould fluxes. In this paper, two kinds of low-fluoride and titanium-bearing mould fluxes with different basicity (R_1·15 and R_1·35) were designed and the lubrication property and heat transfer properties were investigated. Their physical–chemical properties were compared with those of 3D mould flux (F⁻≧7%) used in medium carbon peritectic steel slab casting. The plant trials results indicate that the designed mould fluxes have a normal performance, appropriate consumption and no sticker alarm in the mould; and that the slab surface quality cast by R_1·35 mould flux is comparable to cast by 3D mould flux.

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