Vacuum centrifugal casting method and its device

Abstract

The invention relates to a vacuum centrifugal casting method. The method aims to improve poor conversion proportion between casting materials and castings in a traditional vacuum casting method. The vacuum centrifugal casting method includes the steps that a shell mold is positioned and placed on a rotating platform, the rotating platform is connected to a rotating shaft capable of rotating in the axial direction, and metal ingots are placed on a crucible portion of the shell mold and are heated and melted under the vacuum environment; the rotating shaft is driven to drive the rotating platform to rotate so as to enable molten metal to flow into a mold cavity portion of the shell mold; the cast shell mold is taken down from the rotating platform; the shell mold is destroyed, and a casting is obtained. The invention further discloses a vacuum centrifugal casting device matched with the vacuum centrifugal casting method. By means of the vacuum centrifugal casting method and device, the violent oxidizing reaction generated by the molten metal is avoided, the convention proportion between the casting materials and the castings can be improved, the waste of the casting materials is avoided, the casting yield can be improved effectively, and casting cost can be reduced effectively.

Description

technical field [0001] The invention relates to a precision casting method and its device, in particular to a vacuum centrifugal casting method and its device. Background technique [0002] Generally speaking, investment casting is mostly carried out in the atmosphere, and the metal ingots are quickly melted with the help of a high frequency induction melting furnace (High Frequency Induction Furnace), and then combined with static gravity casting. However, when the metal ingot contains reactive metals such as aluminum, copper, silver, etc., due to the high activity of the reactive metal to oxygen, it is easy to have a violent oxidation reaction with oxygen during the smelting process, resulting in slag holes or reaction pores in the casting. Defects; on the other hand, the violent oxidation reaction will also cause the fluidity of the molten metal in the shell mold to decrease, and it is easy to reduce the molding yield of the casting due to insufficient casting, or the pro...

AI Technical Summary

Problems solved by technology

However, when the metal ingot contains reactive metals such as aluminum, copper, silver, etc., due to the high activity of the reactive metal to oxygen, it is easy to have a violent oxidation reaction with oxygen during the smelting process, resulting in slag holes or reaction pores in the casting. Defects; on the other hand, the violent oxidation reaction will also cause the fluidity of the molten metal in the shell mold to decrease, and it is easy to reduce the molding yield of the casting due to insufficient casting, or the problem of cold shut (Cold Shut). gap in

[0003] In order to solve the above problems, when the metal ingot contains active metals, the melting process is usually carried out in a vacuum environment. At present, the vacuum casting commonly used in the industry generally includes vacuum arc melting (Vacuum Arc Melting) and induction melting (Induction Shell Melting). Skull Melting) two types; however, whether it is vacuum arc melting or induction shell melting, water-cooled copper crucibles are used as carriers for metal ingot melting during the melting process, but water-cooled copper crucibles will reduce the superheat of the metal (Degree of Superheat), so that the molten metal re-solidifies on the inner surface of the water-cooled copper crucible, and forms a shell with a thickness (the so-called "condensed shell"), so that the proportion of metal ingots converted into castings is reduced, resulting in waste of castings and It is difficult to reduce the cost of casting, especially when the metal ingot contains more expensive components such as titanium, nickel or cobalt, how to increase the conversion ratio between casting materials and castings has become an urgent issue for improvement

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