Abstract During quenching of aluminium alloys from the solutionising temperature vacancies are partially conserved as excess vacancies, partially lost to vacancy sinks, the exact fractions depending on the cooling rate. Positron lifetime measurements in samples from interrupted quenching experiments reveal that vacancies are lost during cooling down to 200 °C, after which solute atoms start to form clusters down to 20 °C. Slow cooling leads to 1 to 2 orders of magnitude lower excess vacancies than fast cooling. Since quenched-in vacancies are crucial for natural ageing (NA) in Al-Mg-Si alloys it is surprising to find just small differences between the NA hardening kinetics after different quenches. Specifically, hardening rates differ only in the initial stage (

中文翻译：

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不同淬火条件下Al-Mg-Si合金的自然时效团簇

摘要 在铝合金从固溶温度淬火过程中，空位部分保留为过量空位，部分损失为空位汇，具体比例取决于冷却速度。来自间断淬火实验的样品中的正电子寿命测量表明，在冷却至 200 °C 的过程中，空位会丢失，此后溶质原子开始在低至 20 °C 时形成簇。与快速冷却相比，缓慢冷却导致过量空位低 1 到 2 个数量级。由于淬火空位对于 Al-Mg-Si 合金的自然时效 (NA) 至关重要，因此令人惊讶地发现不同淬火后 NA 硬化动力学之间的差异很小。具体来说，硬化率仅在初始阶段不同（