| 摘要 |
PURPOSE:To form a billet and ingot having fine crystal structure by dropping the molten metal in a tundish at specific periods from a nozzle, cooling the same with a gas from gas injection nozzles and introducing the liquid drops in a half-melted state into a casting mold. CONSTITUTION:The molten metal 11 in the tundish 12 passes plural pieces of holes 14 provided to a dispensing member 15 from a nozzle 13 and falls in the form of the liquid drops 19 when a stopper 16 is periodically moved up and down by a cylinder 17. The flatting liquid drops 19 are cooled by, for example, gaseous He, etc. ejected from the gas ejection nozzles 24 during the falling and fall in the half-melted state into the casting mold 18. The liquid drops are cooled by the casting mold 18 in the state in which the solid-liquid co-existence phase exists. The ingot 26 having the small crystal grain size of the solidified structure is thus obtd.
|
