| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a continuous casting method for steel which suppresses temperature deviation in the width direction of a slab and overcooling of its surface and which achieves both prevention of internal cracks and prevention of surface cracks of the slab. <P>SOLUTION: In the continuous casting method for steel using a continuous casting machine 12 having a mold 10 and a secondary cooling zone 11, the slab 13 containing by mass, ≥1.0% Si or ≥10% Cr or ≥0.5% C is cooled by cooling nozzles of the secondary cooling zone 11. CaO/SiO<SB POS="POST">2</SB>of powder supplied into the mold 10 is set to 0.90 to 1.45. Out of the secondary cooling zone 11, in a cooling range R1 of up to 0.6 m in the casting direction from directly below the mold 10 and in a cooling range R2 of from 0.6 to 1.2 m in the casting direction from directly below the mold 10, the water quantity densities P1, P2 of the cooling water sprayed from the cooling nozzles to the slab 13 satisfy the conditions of 150 L/m<SP POS="POST">2</SP>/min≤P1≤280 L/m<SP POS="POST">2</SP>/min, and 300 L/m<SP POS="POST">2</SP>/min≤P2≤700 L/m<SP POS="POST">2</SP>/min. <P>COPYRIGHT: (C)2013,JPO&INPIT |
