Ta-contained stress corrosion-resistant Al-Zn-Mg-(Cu) alloy and preparation method thereof

Abstract

The invention discloses Ta-contained stress corrosion-resistant Al-Zn-Mg-(Cu) alloy and a preparation method thereof. The alloy contains main alloying elements of Al-Zn-Mg or Al-Zn-Mg-Cu and microalloying elements of Zr, Ta, Fe and Si; moreover, a mass ratio of the microalloying elements satisfies the conditions that Ta is larger than or equal to 0.1Zr and less than or equal to 0.5Zr, Si is larger than or equal to 0.1Zr and less than or equal to 0.3Zr, and Fe/Si is larger than or equal to 0.7 and less than or equal to 1.5; according to the preparation method of the Ta-contained stress corrosion-resistant Al-Zn-Mg-(Cu) alloy, after an ingot metallurgy method is adopted for preparing the alloy, the alloy is subjected to homogenizing treatment, deformation treatment and solid solution waterquenching, and then artificial ageing is conducted. According to the Ta-contained stress corrosion-resistant Al-Zn-Mg-(Cu) alloy and the preparation method thereof, a multielement microalloying methodis adopted, cooperation of the multielement microalloying elements is strictly controlled to form a multielement coherent dispersed phase, recrystallization is completely inhibited, the microalloyingelements are used for improving the corrosion resistance effect of aluminium alloy passive film, high strength and good corrosion resistance performance are combined, and the problem that the strength and the corrosion resistance of existing Al-Zn-Mg-Cu ultrahigh-strength aluminium alloy cannot be achieved at the same time is solved; the preparation method of the Ta-contained stress corrosion-resistant Al-Zn-Mg-(Cu) alloy is simple in technology, and the Ta-contained stress corrosion-resistant Al-Zn-Mg-(Cu) alloy is suitable for industrialized production.

Description

technical field [0001] The invention relates to a method for microalloying and heat treatment of metal alloys, in particular to a method for improving the stress corrosion resistance of Al-Zn-Mg-(Cu) alloys; (Cu) alloy and preparation method thereof. It belongs to the technical field of metal material preparation. Background technique [0002] Al-Zn-Mg-(Cu) ultra-high-strength aluminum alloys have the advantages of low density, high strength, and easy processing. They are important structural materials for aircraft, rockets, rail transit, and weapons and equipment. extremely important role. However, the high-alloyed Al-Zn-Mg-(Cu) ultra-high-strength aluminum alloys lead to the aggregation of high-density aging precipitates at the grain boundaries, the characteristics of intergranular corrosion fracture are significant, and the alloy stress corrosion resistance is poor, which is the application of this type of aluminum alloy. The problems commonly encountered at times rest...

AI Technical Summary

Problems solved by technology

However, only through the optimization of the aging heat treatment system for Al-Zn-Mg-(Cu) alloys, the precipitated phases of highly alloyed super-strength Al-Zn-Mg-(Cu) alloys will still be enriched at the grain boundaries. The fracture characteristics of crystal corrosion are still significant, and there are great limitations in solving the contradiction between the strength performance and corrosion resistance of alloys. Corrosion resistance is still the bottleneck restricting the development and application of super-strength aluminum alloys.

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