Corrosion-resistant aluminum alloy and preparation method and application thereof

Abstract

The invention belongs to the field of metal material preparation, and discloses a corrosion-resistant aluminum alloy and a preparation method and application thereof. The corrosion-resistant aluminumalloy comprises, by weight percentage, 0.8-1.2% of Mg, 0.9-1.3% of Si, 0.1-0.3% of Cu, 0.2-0.4% of Mn, 0.15-0.35% of Cr, 0.1-0.3% of Zr, 0.2-0.6% of Hf and less than or equal to 0.5% of Fe. Accordingto the corrosion-resistant aluminum alloy and the preparation method and application thereof, a trace of Hf, Zr and Cr elements are added, a three-stage homogenization process is adopted, so that theprecipitation of a saturated matrix is promoted to form a high-stability (Al, Cr) 3 (Hf, Zr) phase, the growth of recrystallized grains is inhibited, the grains are refined, and the corrosion resistance of the alloy is improved; a high-density (Al, Cr) 3 (Hf, Zr) dispersed phase is formed, so that the strength of the alloy is further improved; by optimizing the contents of Mg, Si and Cu elements,the Mg / Si ratio and the like, Cu-Si and a vacancy form an early aging cluster, dispersion and precipitation of a strengthening phase are promoted, the content of an aging strengthening phase (Mg2Si) is increased, and the alloy achieves high strength; and a proper amount of Cu element is also added, meanwhile, a Q phase, a theta phase and other Cu-containing phases are prevented from being formed,and excellent corrosion resistance can be obtained. The obtained aluminum alloy is suitable for being used as aluminum alloy for automobile structural components or applied to other profiles.

Description

technical field [0001] The invention belongs to the field of metal material preparation, and in particular relates to a corrosion-resistant aluminum alloy and a preparation method and application thereof. Background technique [0002] 6xxx series aluminum alloys (i.e. Al-Mg-Si series alloys), due to their medium to high strength and high formability, have become the preferred materials for the new generation of lightweight vehicles. AA6016, AA6111 and AA6022 alloys are used in the processing of automobile body outer panels, and are widely used in body aluminum alloys. In order to improve the strength of Al-Mg-Si aluminum alloys, the content of Mg, Si, and Cu elements is usually increased, but this not only reduces the plasticity and corrosion resistance of the alloy, but also greatly reduces the processing performance of the alloy. At this time, it is usually necessary to control the content of Mg and Si elements to obtain high formability properties of the alloy. In the p...

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Problems solved by technology

Sc element is the most effective rare earth element to inhibit the recrystallization of aluminum alloy, obtain non-recrystallized structure, and form secondary dispersed Al 3 Sc phase improves alloy strength and stress corrosion resistance, but the high cost limits the industrial application of Sc-containing rare earth aluminum alloys

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