| 摘要 |
PURPOSE:To obtain an aluminized steel sheet having improved mechanical properties by rapidly cooling an aluminized steel sheet in two steps immediately after aluminizing and by carrying out annealing and skin pass rolling to remove spangle on the Al surface. CONSTITUTION:A steel sheet aluminized in an aluminizing bath is pulled up from the bath, and the amount of Al stuck is controlled by gas wiping. The aluminized steel sheet is rapidly cooled until the stuck Al is solidified to form fine spangle, and it is rapidly cooled to <=450 deg.C at 30-100 deg.C/sec cooling rate. The steel sheet is then subjected to overage annealing at 350-450 deg.C, and it is passed through a skin pass rolling mill to remove the fine spangle on the Al surface. By this method the spangle is perfectly removed by passing the steel sheet through the mill once, and an aluminized steel sheet having superior mechanical properties is obtd. |
