7xxx系铝合金回归再时效的研究现状

7xxx系铝合金作为高强度铝合金的代表,以其较高的强度以及良好的韧性和耐蚀性等优异性能而广泛地应用于航空航天及交通运输领域.该类可热处理强化铝合金对微观组织结构敏感,其性能受合金内部析出相的形核、生长及分布情况的影响.采用三级时效工艺—回归再时效处理,通过预时效、回归、再时效3个过程的有效配合改变合金的析出相状态,可以...

Research status of regression and reaging on 7xxx series aluminum alloy

As a representative high-strength aluminum alloy, the 7xxx series aluminum alloy has been widely used in aerospace and transportation fields for its high strength, good toughness and corrosion resistance and other excellent properties. This kind of heat treatable aluminum alloy is sensitive to microstructure, and its properties are affected by the nucleation, growth and distribution of precipitates in the alloy. Its mechanical properties and corrosion resistance could be well combined by using the three-stage aging process-retrogression and reaging treatment-to change the precipitate state through the effective combination of preaging, retrogression and reaging. At present, many studies of its application on the 7xxx series aluminum alloy have been conducted, and some progress has been made. In this paper, the method of retrogression and reaging treatment was first introduced, and its effect on the microstructure and properties of 7xxx series aluminum alloy was then overviewed. Finally, the research status in this field was summarized.