| 摘要 |
PURPOSE:To produce a cast strip having fine crystallized grains by running the cast strip cast with cooling drums under the condition in contact with the drum surface, rapidly cooling and rolling with hot-rolling at the specific draft. CONSTITUTION:Molten metal in pouring basin part 2 grows as solidified shell on peripheral surface of the cooling drums 1a, 1b by conducting heat through the cooling drums 1a, 1b to be drawn as the cast strip 3. Then, the cast strip 3 is run under the condition of being pushed to one side of the cooling drum 1a with a pushing roll 4 and rapidly cooled in the temp. range of 1,250 - 1,100 deg.C at >=200 deg.C/sec cooling velocity. In this process, coarsening of crystallized grains is restrained. The cast strip 3 is fed into rolling rolls in the hot-rolling mill 5 as it is comparatively fine crystallizing condition, and the hot rolling is executed at <=40% draft according to cooling velocity to the rolling temp. This cast strip has <=about 50mum grain diameter of gamma grain and in the following process, the product without surface defect of roping and uneven glossiness, etc., can be obtd. |
