| 摘要 |
PURPOSE:To produce easily a billet having fine crystal structure by providing a coil around a nozzle, supplying high-frequency current to the coil and turning on and off the supply of the current at prescribed time intervals. CONSTITUTION:An alternating magnetic field around the coil 7 is generated around the coil 7 when the high-frequency current is supplied from a high-frequency power source 8 to the coil 7. Eddy current is then passed through the molten metal 4 flowing in the nozzle 6 in the direction opposite from the direction of the current flowing in the coil 7. As a result, the electromagnetic force toward the axial center direction is acted to the molten metal 4 flowing in the nozzle 6 by the alternating magnetic field and the eddy current. The outflow of the molten metal 4 from the nozzle 4 is therefore thoroughly stopped by increasing the magnitude of the high-frequency current to be conducted to the coil 7. The molten metal drops 11 fall from the nozzle 6 into a casting mold 11 when the conduction of electricity to the coil 7 is turned on and off at the prescribed time intervals.
|
