High-efficiency continuous casting method of structure-controllable closed cell foam aluminum ingot

Abstract

The invention discloses a high-efficiency continuous casting method of controllable structure-controllable closed cell foam aluminum ingot, belonging to the technical field of continuous porous metal preparation. According to the method, the decomposition control on a foaming agent in a melting body is realized by changing the treatment means of the foaming agent, the continuous production not only greatly improves the production efficiency but also solves the problem of bubble-free layers during static casting, and the continuous production of the closed cell foam aluminum ingot is achieved by controlling the casting temperature, the casting speed and the cooling intensity in a continuous casting process; the sizes and the shapes of bubbles in an aluminum substrate are controlled by adding foaming agents which have different types, different additive amounts and different particle sizes and are subjected to different pretreatments, and a control method of the porous structure is relatively high in realizability and relatively meets the requirements on the product diversity in actual application. The method is simple in process and low in cost, achieves the continuous casting, greatly improves the production efficiency, relatively meets the industrialized requirements and can be used for efficiently and continuously preparing large-sized closed cell foam aluminum ingot.

Description

technical field [0001] The invention relates to a high-efficiency continuous casting method for a closed-cell foamed aluminum ingot with a controllable structure, and belongs to the technical field of continuous preparation of porous metals. Background technique [0002] Aluminum foam has ultra-low density, high specific strength / specific stiffness, and excellent properties such as sound absorption, impact resistance, flame retardancy, and electromagnetic shielding, so it can be used as a lightweight structure and vibration damping medium for aerospace, weaponry, and automobiles It can also be used as a functional material in highway sound insulation, building noise reduction, and electronic instrument electromagnetic wave protection. At present, the commonly used methods for preparing aluminum foam include infiltration casting, investment casting, electrolytic deposition, solid-gas eutectic solidification, powder metallurgy, gas injection foaming, and melt foaming. [0003...

AI Technical Summary

Problems solved by technology

U.S. Patent US.pat.3743353 described with TiH 2 When used as a foaming agent to prepare foamed aluminum, the stirring and foaming time is required to be controlled within 1 to 2 minutes, which greatly increases the difficulty of the preparation operation, and the application in continuous casting is less achievable;

[0010] (2) There is no bubble layer in static casting

At present, in static casting, there will be a solid body with a certain thickness at the bottom of the foam. Although the non-foaming layer at the bottom can be reduced by adding a wetting agent such as Mg, it cannot be completely eliminated;

[0011] (3) Currently available equipment and processes are complex and difficult to operate

Although this patent realizes semi-continuous casting of aluminum foam prepared by melt foaming method, its equipment structure and process are still very complicated. Although it improves production efficiency to a certain extent, it is still not as high as the continuous casting method;

[0012] (4) It can only be operated intermittently, not continuous casting in the true sense

The method described in the Chinese patent CN1320710A improves foreign patents, which reduces the difficulty of foam aluminum operation, but this method belongs to gap operation, the efficiency is not high, and it is difficult to prepare large-scale aluminum foam products;

[0013] (5) Different batches of products are difficult to guarantee stable quality

US patent US.pat6984356B2 and Chinese patent ZL200610032465.0 respectively describe a continuous preparation method and continuous foaming equipment for aluminum foam. Although these two patents can realize low-cost continuous production of aluminum foam, it is difficult to prepare large-scale aluminum foam. Aluminum foam products

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