Preparation method of ultrahigh-strength aluminum alloy with high creep resistance

Abstract

The invention discloses a preparation method of an ultrahigh-strength aluminum alloy with high creep resistance. The preparation method comprises the following steps: obtaining a prefabricated alloy ingot; wherein the alloy ingot comprises the following components in percentage by mass: 10.0 to 13.0 wt% of Zn, 1.9 to 3.2 wt% of Mg, 1.2 to 2.2 w wt% of Cu, 0.02 to 0.2 wt% of Ti, 0.1 to 0.2 wt% of Zr, 0.1 to 0.3 wt% of Sc, less than or equal to 0.05 wt% of Fe and less than or equal to 0.05 wt% of Si, Fe is greater than Si, and Al is an equilibrium element; under the inert gas condition, induction melting is conducted on the alloy ingot, and after molten alloy liquid is evenly mixed, atomization spray deposition is conducted to obtain a billet; the billet is extruded into a bar in an isothermal extrusion mode; and the bar is subjected to two-stage solid solution heat treatment, the bar subjected to heat treatment is subjected to quenching treatment, and the finished aluminum alloy is obtained. After hot extrusion, the alloy is completely densified, the room-temperature and high-temperature creep resistance of the alloy is greatly improved compared with a traditional ultrahigh-strength aluminum alloy, and the application prospect of the alloy is greatly expanded.

Description

technical field

[0001] The invention relates to the technical field of aluminum alloy preparation, in particular to a method for preparing an ultra-high-strength aluminum alloy with high creep resistance. Background technique

[0002] Al-Zn-Mg-Cu series (7XXX series) alloys are widely used in aerospace, weaponry and other fields due to their high strength, low density and many other advantages. As a structural material, its service life is required to be as long as more than ten years under some specific working conditions, and its working environment belongs to the generalized creep environment. At present, there are nearly a hundred kinds of Al-Zn-Mg-Cu series aluminum alloys of various composition grades that have been developed in the world, and the corresponding alloy heat treatment standards are also divided into categories, but there is still no system for the creep life of ultra-high-strength aluminum alloys. research and evaluation. Contents of the invention [...

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