Grain refiner and application of grain refiner in aluminum alloy wheel hub

Abstract

The invention relates to a grain refiner and an application of the grain refiner in an aluminum alloy wheel hub. The grain refiner is characterized by being prepared through the following steps: (1) preparing powdery Al, Ti and B participating in the reaction according to mass percents of 65-75%, 15-30% and 5-10%; (2) smelting an aluminum ingot containing 6.5-7.5% of silicon and 0.3-0.45% of magnesium, adding a covering agent and a refining agent, degassing and stewing to obtain a matrix alloy fused mass; and (3) putting reaction blocks in an electromagnetic induction furnace for heating and drying, pressing the reaction blocks into the fused mass according to 5-10% by mass of the matrix melt through an immersion bell in batches, keeping the temperature for 20 min to perform thermal explosion synthetic reaction on the reaction blocks in the fused mass so as to crack and disperse the reaction blocks due to strong heat release, and mechanically stirring the fused mass to completely dilute the synthetic product and disperse the synthetic product in the aluminum fused mass. The solution and diffusion periods of the TiAl3 phase of the aluminum alloy solution prepared by the method are greatly reduced, the dispersibility of the TiB2 particles is greatly improved to facilitate the refining function, and the size of the casting crystalline grain of an intermediate alloy can be effectively controlled to be lower than 40 microns.

Description

technical field [0001] The invention relates to a grain refiner and its application in an aluminum alloy wheel hub, belonging to the technical field of metal materials. The prepared grain refiner can refine the aluminum alloy grains, and significantly improve the strength and toughness. Background technique [0002] Due to its light weight, high specific strength, corrosion resistance, good electrical and thermal conductivity, and easy processing, aluminum alloys are widely used in machinery, aerospace, automobiles, and other fields. However, because the alloy is easy to form a coarse grain structure under casting conditions, in order to realize its wide application, it is necessary to improve its as-cast structure and then improve its performance. At present, in the industrial production of aluminum alloy, the method of adding Al-Ti-B master alloy to the melt is generally used to achieve the purpose of grain refinement, and the preparation of Al-Ti-B master alloy is genera...

AI Technical Summary

Problems solved by technology

Although the master alloy can have a certain refining effect on aluminum alloys, the preparation cycle of the master alloy is long, the energy consumption is large, the oxidation and burning of the metal is serious, and the intermetallic compound TiAl in the alloy structure 3 The particles are generally relatively coarse, and the size is above 80 μm, which increases the response time of the master alloy

And TiB 2 The dispersion of the particle aggregates is poor, so that the refinement performance of the master alloy cannot achieve the desired effect