COOLING DRUM FOR THIN SLAB CONTINUOUS CASTING, PROCESSING METHOD AND APPARATUS THEREOF, AND THIN SLAB AND CONTINUOUS CASTING METHOD THEREOF

摘要

Hollows, preferably hollows, each having an average depth of 40-200 .mu.m an d a circle-equivalent diameter of 0.5-3 mm, are formed on the peripheral surfa ce of a cooling drum, the hollows being formed adjacent to one another via the tops of the hollows; and on/in the tops and /or the surfaces of the hollows are formed minute projections (preferably, minute projections 1-50 .mu.m in height and 5-200 .mu.m in circle-equivalent diameter on the surfaces of the hollows, and those 1- 50 .mu.m in height and 30-200 .mu.m in circle-equivale nt diameter on the tops of the hollows), and small holes (preferably, small hol es at least 5 .mu.m in depth and 10-200 .mu.m in circle-equivalent diameter) or minute irregularities (preferably, minute irregularities 1-50 .mu.m in avera ge depth and 10-200 .mu.m in circle-equivalent diameter).