| 摘要 |
PURPOSE:To improve the corrosiveness of a horn applied with ultrasonic oscillations and to fine crystal grains in continuous casting of belt wheel type by evacuating the inside of a vessel immersed and inserted into charged molten metal to form a well and inserting said horn therein. CONSTITUTION:In the stage of continuous casting of belt wheel type for Al, etc., an inverted cup-like vessel 9 of sealed type formed of a heat insulating material is immersed and inserted into the upper part of a tundish 4. The inside of the vessel 9 is evacuated by operating an evacuating pump to form an evacuated chamber and to heighten the surface 5' of the molten metal upward to a constant level and to hold the same at said level, thereby forming a well 8. A horn 7 is inserted into the well 8, and ultrasonic oscillations are applied thereto. The metal 5 in the tundish 4 is charged into a mold consisting of a rotary wheel 1 for casting, endless belts 2, 2', and a pressing wheel 3, whereby the molten metal is cooled and solidified to form a cast ingot 6. By such method, the crystal grains of the cast ingot are fined stably for a long time without using any additive. |
