(1.廣西大學物理系，南寧 530004;
2.中國科學院金屬研究所，沈陽 110015)
摘 要: 在深低溫到室溫不同溫度下，測量了不同時效狀態(tài)的Al-Li-Cu-Mg-Zr合金和含Zn 、Ag或Sc的合金的正電子壽命譜。分析表明：峰值時效使熱空位大量回復并使基體電子密度提高。在深低溫下，空位主要以單空位形式存在且隨溫度升高而激活并運動復合成多空位。Zn和Ag對空位的運動有束縛作用，Sc有助于空位的運動。樣品在低溫下基體電子密度升高，對合金低溫強度產(chǎn)生重要影響。
關(guān)鍵字: 深低溫 正電子壽命譜 Al-Li-Cu-Mg-Zr合金 缺陷
（1.Physics Department, Guangxi University, Nanning 530004;
2.Institute of Metals Research, Chinese Academy of Sciences, Shenyang 110015）
Abstract:At the variant points from cryogenic to ambient temperature, the positron annihilation lifetime spectra of Al-Li-Cu-Mg-Zr alloy added with or no Zn, Ag, Sc at different ageing conditions were measured. The analyses for lifetime spectra show that a large number of thermal vacancies are recovered and the bulk electronic density increases during the peak-ageing process. At the cryogenic temperature the vacancies are mainly monovacancies, while with the temperature increasing they become activated and move to combine into multivacancies. The doping of Zn or Ag will hinder the movement of monovacancies but that of Sc is available to the movement. The bulk electronic density in all samples at low temperature is higher than that at ambient temperature, which has important influence on the low temperature strength of alloys.
Key words: cryogenic temperature positron lifetime spectrum Al-Li-Cu-Mg-Zr alloy defects
