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采用透射电镜（ＴＥＭ）和Ｖｉｃｋｅｒｓ硬度计研究了Ａｌ－Ｚｎ－Ｌｉ－Ｍｇ－Ｃｕ合金在４３３Ｋ的人工时效行为结果表明，在等温时效动力学曲线上存在双阶段硬化行为。第一阶段硬化起因于合金基体上沉淀析出的 相（ＡｉＬｉ），时效强化效果来自相；随着时效的进行，到达第二时效硬化峰，在合金基体上除了δ相外，大量析出一种具有准晶结构的沉淀硬化相（命名为Ｘ相）；此时，时效强化效果来自 相和Ｘ相。在Ｘ相的周围存在无δ相析出区，表明Ｘ相含有Ｌｉ原子。Ｘ相呈棒状，棒的长轴与基体的〈１１０〉Ａｌ方向一致。ＥＤＳ测试表明，Ｘ相富集Ｃｕ，Ｚｎ和Ｍｇ．
The artificial aging behavior of Al-Zn-Li-Mg-Cu alloy at 433K was investigated by transmission electron microscopy (TEM) and Vickers hardness tester. The results show that there are two-stage hardening behavior in the isothermal kinetic curve. The first stage hardening results from precipitation of precipitated phase (AiLi) on the alloy matrix, and the aging strengthening effect comes from the phase. As the aging progresses, the second age hardening peak arrives, and in addition to the δ phase on the alloy matrix, Quasi-crystalline precipitated hardened phase (named X-phase); at this time, the strengthening effect from the phase and phase X phase. There is no δ precipitation in the vicinity of the X phase, indicating that the X phase contains Li atoms. The X phase is rod-shaped and the long axis of the rod coincides with the <110> Al direction of the substrate. EDS tests show that phase X is enriched in Cu, Zn and Mg.