| 摘要 |
PROBLEM TO BE SOLVED: To produce a hot-rolled steel sheet of a high phosphors steel difficult to develop crack when a cold-rolling is applied. SOLUTION: The apparatus is provided with a drum caster 4 for casting molten high phosphorus steel 11 into a cast strip 12 at >=50 K/sec cooling speed and a hot-rolling mill 6 for hot-rolling the cast strip 14 into a hot-rolled strip 15. The hot-rolling mill 6 is provided with two work rolls 31, 32 hot-rolled in contact with the cast strip 14 and cross anglesθ,θ' formed with rotating shafts 41, 42 in the work rolls 31, 32 to the width direction D are 2 degrees or larger. This casting is prevented from segregating the phosphorus in crystal grain boundary, and this hot-rolling, in which a shearing strain quantityεD in the width direction of the hot-rolled strip 15 is made 0.2 or larger is applied to prevent the crack when the hot-rolled strip 15 is cold-rolled.
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