Preparation method of submicrocrystal ultra high strength aluminium alloy

Abstract

A process for preparing ultrahigh-strength submicron-crystal aluminium alloy 2000 or 7000 includes such steps as annealing Al alloy, squeezing by equal pathway angle 2-6 times, solid dissolving at 450-500 deg.C, squeezing by equal pathway angle 2-4 times, and natural ageing. An another process is also disclosed. Its advantages are high tension strength 100-150 MPa, better toughness, and super plasticity.

Description

Technical field [0001] The invention belongs to the technical field of nonferrous metal material processing, and in particular relates to a preparation method of a submicrocrystalline ultrahigh-strength aluminum alloy. Background technique [0002] The Equal channel angular pressing or extrusion method was proposed by Segal and his colleagues. They designed such a mold so that the sample passes through two equal-section channels that form a Ф angle under pressure. , at the interface of the two channels, under the action of shear force, the crystal grains are refined to sub-micron level, and the material properties are improved. For aluminum and aluminum alloys, equal channel angular extrusion is generally used after annealing. At present, the 2000 series aluminum alloys used in the aerospace field are conventionally processed into plates and subjected to solid solution at 490 ° C, and used after natural aging. After solid solution at ℃, artificial aging is carried out, and...

AI Technical Summary

Problems solved by technology

However, the performance of the annealed aluminum alloy through equal channel angular extrusion, although the grain reaches submicron level, cannot meet the requirements of the aerospace industry, and the general large-grain aluminum alloy can reach high after solid solution aging treatment. Strength, less than ultra-high strength, and prone to low stress fracture