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在深低温到室温的不同温度下，测量了不同时效状态的Ａｌ－Ｌｉ－Ｃｕ－Ｍｇ－Ｚｒ合金和含Ｚｎ，Ａｇ或Ｓｃ的Ａｌ－Ｌｉ－Ｃｕ－Ｍｇ－Ｚｒ合金的正电子寿命谱。对ｅ＋寿命谱特征参数的分析表明：峰值时效使热空位大量回复，缺陷的数目减少。在深低温下，空位主要以单空位形式存在且随温度升高而激活并运动复合成多空位。Ｚｎ或Ａｇ的加入对空位的运动复合有束缚作用，而Ｓｃ却有助于空位的运动复合。所有实验样品低温下基体电子密度都比室温的高，δ＇相析出长大使合金基体的电子密度提高，而Ｓ＇相析出则使合金基体的电子密度降低。Ｚｎ，Ａｇ或Ｓｃ的加入都增加了基体电子密度，有利于合金强度的提高。
The positron lifetime spectra of Al-Li-Cu-Mg-Zr alloys and Al-Li-Cu-Mg-Zr alloys containing Zn, Ag or Sc were measured at different temperatures from room temperature to room temperature. The analysis of the characteristic parameters of the e + lifetime spectrum shows that: the peak aging causes a large number of hot vacancy recovery, the number of defects reduced. At cryogenic temperatures, vacancies predominate as single vacancies and are activated with increasing temperature and recombine into multiple vacancies. The addition of Zn or Ag has a binding effect on the movement of vacancies, while Sc contributes to the kinematic recombination of vacancies. The electron density of the matrix was higher than that at room temperature in all the samples. The δ ’phase precipitated and grew up, which increased the electron density of the alloy matrix, while the S’ phase decreased the electron density of the alloy matrix. The addition of Zn, Ag or Sc both increases the electron density of the matrix, which is favorable for the improvement of the alloy’s strength.