| 摘要 |
PURPOSE:To form stably an ingot having unidirectionally solidified structure by positioning the solidification front to be formed in a nozzle mold lower than the bottom end of a hollow water cooling jacket and executing pressure casting under the condition under which the shape thereof is made into a projecting surface shape. CONSTITUTION:A crucible 6 is raised by a crucible lifting cylinder 14 to immerse the bottom end of the nozzle mold 8 into molten copper 10, by which a seed ingot inserted preliminarily into the mold 8 through the aperture at the top end of the hollow cooling water jacket 9 is brought into contact with the molten copper 10. A valve 4 is closed and a valve 5 is opened in this state to introduce gaseous Ar through a gaseous Ar introducing pipe 3 into a pressurizing chamber 1. The distance between the jacket 9 and the top surface of the copper 10 is maintained at the prescribed distance and the seed ingot is pulled up intermittently at a prescribed rate by pinch rolls by which the pure copper ingot 11 is formed. |
