A performance optimization method for ultra-high-strength aluminum alloy blanks

Abstract

A performance optimization method for an ultra-high-strength aluminum alloy billet, the performance optimization method comprising: putting the ultra-high-strength aluminum alloy billet into a heat treatment furnace for heat preservation and solution treatment, then taking it out of the heat treatment furnace for water-cooling quenching; The ultra-high-strength aluminum alloy billet is clamped and clamped to the stretching machine for pre-deformation treatment; the pre-deformed ultra-high-strength aluminum alloy billet is placed in an aging furnace for pre-aging treatment; the pre-aged ultra-high-strength aluminum alloy billet is processed After the peak aging treatment, it was taken out from the aging furnace and air-cooled to room temperature. The present invention adopts a multi-stage aging process to replace the traditional peak aging (T6) process, and combines pre-deformation to control the size and distribution of precipitated phases, accurately regulates the microstructure of the peak aging state, and comprehensively optimizes mechanical properties. Compared with the conventional single-stage aging process, this method increases the elongation of the material without reducing the strength, significantly improves the mechanical properties, and broadens the application range of the material.

Description

technical field [0001] The invention relates to the technical field of aluminum alloy processing, in particular to a method for optimizing the performance of an ultrahigh-strength aluminum alloy blank. Background technique [0002] Aluminum alloy is a structural material widely used in the aviation field. At present, the aluminum alloy load-bearing structural materials used in the aviation industry mainly include 7075 and 7050 with a strength of more than 500MPa, and 7150 and 7055 with a strength of more than 600MPa, such as medium and high strength Al-Zn-Mg- Cu alloy. However, the strength of highly alloyed Al-Zn-Mg-Cu alloy (Zn content>10%wt.) can exceed 800MPa, which is increased by 30-60%. If the application of ultra-high-strength aluminum alloys on aeronautical structural parts can be realized, the structural weight can be significantly reduced, which is of great significance to the realization of lightweight aeronautical structures. [0003] Al-Zn-Mg-Cu alloy is a...

AI Technical Summary

Problems solved by technology

[0004] Since the degree of alloying of ultra-high-strength aluminum alloys (such as Zn>10wt.%) is much higher than that of 7075, 7050 (Zn, 5.1-6.7wt.%), 7055 (Zn, 7.6-8.4wt.%) and other medium-high-strength Al -Zn-Mg-Cu alloy, the supersaturation of the solid solution state is greatly increased, and it has a stronger driving force for precipitation and a faster atomic diffusion rate during the aging process, which is easy to cause the precipitated phase that has nucleated to be at a higher Coarsening at high temperature is extremely detrimental to the size control of precipitated phases; at the same time, under the single-stage aging system, it is easy to promote the segregation of alloying elements to the grain boundary area, resulting in a widening of the grain boundary without precipitation, resulting in the alloy being easily deformed during deformation. Intergranular cracking occurs, reducing deformability

Therefore, the use of a single-stage peak aging process is not conducive to the precise control and performance optimization of high-saturation ultra-high-strength aluminum alloy precipitates, and it is urgent to develop a new aging process

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