No abstract

No abstract

Synopsis The authors highlighted the small spot segregation present in the center portion of a continuously cast slab, i.e., the semi-macroscopic segregation, and carried out various studies on the subject. The center portion of daily-cast slabs was first investigated in detail. The results reveal that the semi-macroscopic segregation is present in hightemperature cast slabs as well as in low-temperature cast ones. Concentrations of chemical components were measured by EPMA to demonstrate the far higher degree of segregation of semi-macroscopic segregation as compared with that of microscopic segregation, and the dependency of segregation ratio on the size of spot-segregation. Application of soft-reduction casting proved the possibility of reducing the spot size of semi-macroscopic segregation, decreasing the number of spots, and minimizing segregation of constituent elements. By driving a steel pin enclosing tracer element into the center portion of slab, application of soft-reduction casting proved prevention of molten steel from flowing toward the end of solidification crater, resulting in a reduced semi-macroscopic segregation.

No abstract

No abstract