Defect control method in solidification of molten aluminum alloy

Abstract

The invention discloses a defect control method in solidification of a molten aluminum alloy. The defect control method consists of a melting process control method and a solidification insulation control method, wherein the melting process control method includes a molten aluminum gas content control method and a slag inclusion control method; and the solidification insulation control method includes a riser feeding method, a sequential solidification method and a crack control method. The defect control method comprehensively uses gas and slag removal, riser feeding, sequential solidification and aging treatment methods, can effectively reduce the solidification defect probability in cast aluminum alloy, improves the mechanical performances of the cast aluminum alloy, and widens the application range of the cast aluminum alloy.

Description

technical field [0001] The invention relates to the field of aluminum-based alloys, in particular to a defect control method during solidification of molten aluminum alloys. Background technique [0002] Casting is one of the most important methods of manufacturing aluminum alloys. Casting aluminum alloy includes two major steps: smelting of charge and casting of molten aluminum. Among them, the most important process and technology control means during furnace charge smelting can be summarized as: removal and control of dissolved hydrogen and impurity gases, control of molten aluminum refining and effective control of oxide inclusions. The most important process of molten aluminum casting includes: casting control technology, solidification defect control technology and thermal stress control technology. [0003] Due to the high chemical reactivity of aluminum with hydrogen and oxygen, it is easy to dissolve part of hydrogen in molten aluminum and oxidize to form alumina ...

AI Technical Summary

Problems solved by technology

When the molten aluminum is cast in the metal mold, due to the unreasonable mold design, it is prone to insufficient pouring, which makes the shape of the casting incomplete; after casting, during the solidification process of the casting, due to insufficient feeding and the influence of the solidification sequence , in the formed castings, it is easy to have obvious shrinkage porosity in the middle and widely distributed shrinkage cavities, resulting in defective products; and in the process of forming normal temperature aluminum alloy castings from the high temperature molten aluminum solidification, due to the huge temperature difference, the castings Considerable structural thermal stress remains, which is easy to form thermal cracks and reduce the bearing capacity of aluminum alloy

[0005] For the above-mentioned casting defects such as pores, slag inclusions, insufficient pouring, shrinkage cavities and hot cracks, it has an extremely adverse impact on the quality of aluminum alloy castings, and they seriously reduce the performance and service life of cast aluminum alloys. Therefore, major defects must be avoided by appropriate regulatory methods

[0006] Chinese patent CN201310409391.8 discloses an aluminum alloy casting molding process, which reduces the solidification defect rate of castings by spraying paint on molds and low-pressure casting, but this method has high requirements for castings, and the use efficiency is low and the control level is poor