| 摘要 |
PURPOSE:To perform the hot rolling work without permitting the increased AlN precipitation to make the solid solution, and to contrive the energy saving and the improvement of the product quality, by cooling the hot cast slab obtained by the continuous casting of the aluminum killed molten steel to the specified temperature, and by subjecting the slab to the edging pass to give a specified rolling reduction. CONSTITUTION:The cast slab, being obtained by the continuous casting of the aluminum killed molten steel and already finished the solidification, is cooled to temperature lower than Ar3 transformation point and above 500 deg.C in order to thoroughly precipitate AlN; besides, if necessary, the low temperature zone on both sides (edges) is rolled by the edging pass to give a 50mm./pass or larger reduction; hereby, the amount of AlN precipitation is very high level and the AlN precipitation is uniformly distributed, so that the softening of the steel material is economically improved, and also, the workability is improved. |
