SPHERICAL GRANULE MOLD POWDER FOR CONTINUOUS CASTING OF STEEL

摘要

PROBLEM TO BE SOLVED: To provide spherical granule mold powder for continuous casting of steel, capable of improving degradation of heat-retaining property of molten steel in conventional spherical granule mold powder and capable of enhancing the heat-retaining property without impairing the melting characteristics and the operability.SOLUTION: In spherical granule mold powder for continuous casting of steel, particles constituting the mold powder have the following particle size distribution of (1) grain size of <106 μm:<5 mass%; (2) grain size of ≥106 μm and <300 μm: 25-50 mass%; (3) grain size of ≥300 μm and <500 μm: ≤40 mass%; (4) grain size of ≥500 μm and <710 μm: 10-30 mass%; and (5) grain size of ≥710 μm : <5 mass%.