HOT ROLLING METHOD FOR HARD-TO-WORK MATERIAL

PURPOSE:To allow the efficient rolling of a hard-to-work material even in a tandem line without using a reverse rolling or 2 cold rolling and 2 annealing method by heating a material to be rolled which is the hard-to-work material in a coil state at a low temp. and subjecting the material to warm rolling in a specific temp. range. CONSTITUTION:The material to be rolled is heated at the low temp. in the coil state and is then warm rolled at 70 to 200 deg.C at the time of rolling of the hard-to-work material, such as electrical steel sheet, by using tandem mills for cold rolling, etc. Dummy materials are preferably connected to the front end and rear end of the material to be rolled prior to the above-mentioned low-temp. heating. The heating of the coil is preferably executed in a nonoxidative or weakly reducing atmosphere. The efficient rolling is executed in this way and the cooling in the inner and outer peripheral parts of the coil before the rolling after the heating is adequately prevented by the connection of the dummy materials.