1987 Volume 73 Issue 3 Pages 498-504
The effect of reducing heat flux density in continuous casting mould on the solidified shell formation has been studied in order to improve the irregularity of solidified shell thickness and to reduce longitudinal surface cracks. From theoretical considerations, mild cooling in the mould can be attained by making many grooves on the mould inner surface, since the heat transfer coefficient between the strand shell and the mould is lowered due to the air gap existence in the groove. Therefore the width of each groove should be minimized to prevent the molten powder from flowing into the groove.
Experiments using the mould with small longitudinal grooves have been carried out in the curved continuous casting machine. From results of temperature measurements in the copper mould, the local heat flux density at 15mm below the mould meniscus is lowered to about two thirds of that of the conventional smooth surface mould. Both the irregularity of shell thickness and the surface quality of slabs are considerably improved.
