Aluminium alloy refiner and preparation method and application thereof

Abstract

The present invention provides an aluminium alloy refiner. The aluminium alloy refiner is characterized by comprising 7 to 10 parts of Ti, 2 to 3 parts of B and the balance of Al by weight, for example, 8 parts of Ti, 3 parts of B and 89 parts of Al by weight. The aluminium alloy refiner is prepared by rapid solidification. After the refiner is added to A356.2 aluminium alloy, the grain size of the alloy is significantly reduced than that of the aluminium alloy treated by a conventional refiner. Moreover, the solubility of metals in liquid may be increased due to rapid solidification, such that the refiner is more easily absorbed by the aluminium alloy melt after being added to the aluminium alloy.

Description

FIELD OF THE INVENTION[0001]The present invention relates to the field of aluminium alloy smelting, and particularly relates to an aluminium alloy refiner and a preparation method and application thereof.BACKGROUND OF THE INVENTION[0002]A356.2 aluminium alloy has excellent characteristics such as good fluidity, no thermal cracking tendency, low linear shrinkage, small specific gravity and good corrosion resistance, and is a main material used in automobile hubs. However, the as-cast structure of the A356.2 aluminium alloy which is not subjected to refinement and modification treatment is a thickly platy or needle-shaped eutectic silicon and alpha-Al dendritic structure with relatively low mechanical properties. Therefore, it is necessary to add modification elements and grain refining elements, such that morphologies of eutectoid silicon are transformed from thickly flaky shapes or needle shapes into finely spherical shapes or rod shapes, and simultaneously, alpha-Al grains are refi...

AI Technical Summary

Benefits of technology

[0007]Therefore, the present invention aims at providing an aluminium alloy refiner which is relatively low in cost and simple in a use technology.

[0013]In a preferred aspect of the present invention, the aluminium alloy refiner is prepared by rapid solidification.

[0027]Compared with the prior art, the present invention has the following remarkable advantages:(1) the method and equipment for preparation are simple, the alloy smelting and the strip-spun process are smoothly completed, the operation process is simple, the productivity is high, and the disadvantages such as complicated smelting and preparation processes, long process time, limited refining effect and high cost of the raw materials are overcome;(2) the content of Ti and B in the Al—Ti—B alloy prepared by the present invention is higher than that of Ti and B in conventional alloy, the distribution of Ti and B in the Al—Ti—B alloy is more uniform than that of Ti and B in the conventional alloy, the size of Ti and B in the Al—Ti—B alloy is smaller than that of Ti and B in the conventional alloy, and therefore, the quantity of nucleation particles is greatly increased, and the refining effect on the aluminium alloy is relatively good.(3) The present invention does not contain precious metal elements, thus saving the cost of raw materials.(4) The aluminium alloy refiner in the present invention is prepared by a rapid solidification method. Precipitated phase particles are smaller and more evenly dispersed due to rapid solidification. After the refiner is added to the A356.2 aluminium alloy, the grain size of the alloy is significantly reduced than that of the aluminium alloy treated by the conventional refiner. Moreover, the solubility of metals in liquid may be increased due to rapid solidification, such that the refiner is more easily absorbed by the aluminium alloy melt after being added to the aluminium alloy.

Problems solved by technology

However, the as-cast structure of the A356.2 aluminium alloy which is not subjected to refinement and modification treatment is a thickly platy or needle-shaped eutectic silicon and alpha-Al dendritic structure with relatively low mechanical properties.

As the related TiC is nanoparticles, the material cost is high, and a preparation process is complicated.

It is necessary to use argon or nitrogen for dispersing the nanopowder to the melt, which increases the complexity of the process, prolongs the cycle of the whole process and does not facilitate industrial production.

The powder may be used only after the powder is tightly packaged by using aluminum foil and baked for 30 minutes at the temperature of 200-250 degrees Celsius, which increases the complexity of the process and does not facilitate industrial production.

Moreover, the intermediate alloy related in method also comprises 0.1% to 0.5% of noble metal Sc element, and therefore, the manufacturing cost of the Al—Ti—B—Sc intermediate alloy refiner is high.

In summary, the aluminium alloy refiner in the prior art is less likely to be widely applied due to relatively high cost, or the application of the aluminum alloy refiner in production is limited due to complicated using steps and processes.

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