Casting roll for twin roll strip caster

Abstract

Disclosed is a casting roll for a twin roll strip caster, and particularly, a casting roll for a twin roll strip caster, in which a continuous gas channel, for preventing the generation of dents in the surface of a strip when casting TWIP steel in order to improve the mechanical properties of the strip, including increasing the tensile strength and elongation, is formed in the surface of the casting roll, thus discharging gas mixed when the strip is cast, thereby preventing the generation of dents in the surface of the strip when casting the TWIP steel, in particular, a continuous gas channel is formed, thereby decreasing a conventional dent index and discouraging the generation of dents.

Description

TECHNICAL FIELD[0001]The present invention relates to a casting roll for a twin roll strip caster, and more particularly, to a casting roll for a twin roll strip caster, in which a continuous gas channel, for preventing the generation of dents in the surface of a strip when casting TWIP steel in order to improve the mechanical properties of the strip, including increasing the tensile strength and elongation, is formed on the surface of the casting roll, thus discharging gas mixed when the strip is cast, thereby preventing the generation of dents in the surface of the strip when casting the TWIP steel, in particular, a continuous gas channel is formed, thereby decreasing a conventional dent index and discouraging the generation of dents.BACKGROUND ART[0002]In a general twin roll strip casting process, as illustrated in FIG. 1, molten steel 140 in a tundish 130 is supplied between two water-cooling type casting rolls 110, which are rotated in opposite directions, and an edge dam 150 a...

AI Technical Summary

Benefits of technology

[0014]According to the present invention, the casting roll for a twin roll strip caster has a continuous gas channel formed in the surface thereof to discharge gas mixed when casting the strip, thereby preventing the dents from being generated on the surface of the strip when casting the TWIP steel. In particular, because the continuous gas channel is formed, a dent index may be decreased from 3.36%, which is a conventional value, to 0.04% or less, and the sigma level of the generation of dents may be increased from 0.7 to 4.0.

Problems solved by technology

In the case where such TWIP steel is manufactured through a conventional continuous casting process, many cracks are created in the casting process, making it difficult to realize continuous casting.

In particular, upon in-line hot rolling, the production of oxidation scale is non-uniform due to the Mn and Al components contained in greater amounts in the steel, and selective oxidation takes place.

Furthermore, an oxide layer is not completely removed, but adheres on the surface of the roll, undesirably generating many dents.

The dent 161, which is a hemispherical pit having a diameter of 0.5˜3 mm and a depth of 0.1˜1 mm generated in the surface of the strip, partially remains in the surface of the strip even after the rolling process, and is thus a surface defect, undesirably resulting in considerably decreased tensile strength and elongation.

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