Study on Longitudinal Surface Cracks of P and Cu Containing Container Steel CC Slabs

摘要

The fact that the amount of the mold flux components differs at different depth of the cracking surface indicates that the longitudinal surface cracks are initially formed in the mold and was enlarged in the secondary cooling zone. Based on hot ductility measurement of two typical container used steels, it is known that the steels are in severe embrittlement state in temperature range of 825°C - 775 °C. By means of increasing Cr/Ni plating thickness on upper part of the mold, reducing mold heat flux, adopting new secondary cooling pattern, etc., the occurrence of the surface longitudinal cracks on the steel CC slabs has been significantly reduced.