Foamed aluminum with sandwich structure and preparation method of foamed aluminum with sandwich structure

Abstract

The invention provides a preparation method of foamed aluminum with a sandwich structure, and belongs to the technical field of non-ferrous metals. The method comprises the following steps that aluminum alloy powder is mixed with a foaming agent and a thickening agent, after hot pressing or hot extrusion is conducted, a prepared foaming precursor is placed in an aluminum alloy cavity profile withexhaust holes, scaling powder is smeared, foaming is conducted after preheating, and the foamed aluminum with the sandwich structure is obtained. The invention also provides the foamed aluminum with the sandwich structure prepared by the method, and the foamed aluminum can be a special-shaped part. The method has the advantages that the exhaust holes are used for controlling complete filling of the foamed aluminum, the soldering flux is used for improving the interface bonding quality, preheating is used for improving the uniformity of the foaming temperature, and finally the foamed aluminum material with the sandwich structure, which is completely filled and has good interface bonding, is obtained.

Description

technical field [0001] The invention belongs to the technical field of non-ferrous metals, and in particular relates to a foamed aluminum with a sandwich structure and a preparation method thereof. Background technique [0002] Aluminum foam with a sandwich structure has excellent properties such as good vibration damping performance, good noise reduction effect, and high electromagnetic shielding performance. Especially in terms of mechanics, it also has the advantages of low density, high specific strength, high specific stiffness, and good energy absorption capacity. [0003] Aluminum foam with a sandwich structure is a new multifunctional material with a novel structure and a wide range of applications developed in the past 20 years. The usual preparation method of the foamed aluminum part of the sandwich structure is to process the foamed aluminum into shape and then connect it with the solid plate by gluing. However, this method has problems such as poor interface bon...

AI Technical Summary

Problems solved by technology

[0004] However, this method started relatively late, and there are still the following problems in the preparation of aluminum foam with a sandwich structure by the method of the prior art: because the heating of the special-shaped aluminum foam is difficult to be uniform, the heating process of foaming is difficult to be uniform, and the problem of uneven foaming is likely to exist

Because the foaming precursor and the solid aluminum alloy plate are not in full contact before foaming, the surface is oxidized severely during the heating process, making it difficult to break the oxide film between the solid aluminum alloy plate and the foamed aluminum, and it is difficult to achieve metallurgical bonding

There is gas in the solid aluminum alloy cavity, and the gas in some parts cannot be removed, resulting in incomplete filling of foam aluminum

These problems lead to the poor uniformity of the foamed aluminum in the foamed aluminum parts of the sandwich structure, poor interface bonding, and defects such as non-foaming dead angles, which seriously affect product quality.

At the same time, it causes defects such as unstable production process and low yield rate, especially for complex and large-sized special-shaped parts.

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