Abstract: Based on features of peritectic steel continuous casting，a new technical route to ease the contradiction between heat transfer and lubrication was presented. In this work, a high basicity (1.5~2.0) mold flux with high lubrication ability was developed. More than 60 t of new mold fluxes for thick and wide peritectic steel slabs continuous casting were consumed. All the results reveal that the property of this high basicity mould flux is very stable, and no cracks and quality problems were found on slab surface, subsurface or on final product coils, the mould flux consumption is reasonable. The total defect rate of slabs decreased from more than 20% to less than 2%, which proves that the new mold flux has excellent results on easing the contradiction between heat transfer and lubrication.

Key words: peritectic steel, mould fluxes, high basicity, thick and wide slabs