| 摘要 |
PROBLEM TO BE SOLVED: To improve the glossiness of a steel sheet by rolling a steel sheet containing C of not more than a specified rate with a rolling mill having plural stands in which at least the rolling rolls in the front stage are scratch bright rolls having a specified roughness and the rolling rolls in the rearmost stage are bright rolls having a specified roughness. SOLUTION: A steel sheet whose C content is :<=0.012 wt.% is used for that steel sheet. Furthermore, it is preferable to contain 0.005-0.2 wt.% Ti, 0.002-0.1 wt.% Nb and <=0.15 wt.% Al. At least the rolling rolls in the front stage are taken as the scratch bright roll whose roughness Ra is :<=12μm and at least the rolling rolls in the rearmost stage as the bright roll whose roughness Ra is <=0.5μm. The bright rolls having a roll roughness within the range which is divided with the roll roughnesses in the front stage and rearmost stage are suitable to the rolls used at stands other than the front stage and rearmost stage. It is preferable that the temper rolling is executed by dry rolling, its elongation percentage is 1.5±1% and its target hardness is 50-60 by HR30T.
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