| 摘要 |
PURPOSE: A method for enlarging life cycle of mold copper plate for continuous casting using mold flux which has larger thermal resistance is provided to suppress cracking of the copper plate due to thermal strain by lowering heat transfer amount transferred to casting mold from molten steel in a part that is directly under meniscus. CONSTITUTION: The method is characterized in that the copper plate is prevented from being cracked by injecting a mold flux having fast crystallization rate into a continuous casting mold, thereby suppressing a surface temperature of the copper plate of a point that is 205 mm distanced underneath meniscus to 350 deg.C or less, wherein the mold flux comprises 30 to 50 wt.% of CaO, 25 to 40 wt.% of SiO2, 5 wt.% or less of Al2O3, 3 to 8 wt.% of MgO, 5 to 12 wt.% of Na2O and 5 to 10 wt.% of F, and wherein a ratio of Na2O/F is 1.2 to 3.0, a basicity of CaO/SiO2 is 1.1 to 1.7, and crystallizing initiation temperature is 1,150 deg.C or more.
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