| 摘要 |
PURPOSE:To prevent the development of crack in a cast strip by controlling drum diameter casting velocity and molten metal surface height so as to maintain molten metal solidified time to critical solidified time or less. CONSTITUTION:In the relation between metal solidified time (t)(sec) and the critical solidified time tc(sec) showed in the equation I, the drum diameter D(m), casting velocity V(m/min) and the molten metal surface height theta (rad) are con trolled so as to satisfy the inequality t<=tc. By this method, the casting velocity V becomes higher and in this result, the solidified time (t) is shortened to the min. Therefore, the time till coming to the cast strip by separating the solidified shell from the molten metal, is shortened and the difference of growth of the solidified shells is reduced. Therefore, the solidifying shrinkage rate of the solidified shell is reduced and the development of crack in the cast strip is prevented. |
