Al-Mg-Si alloys with total solute contents ranging from 0.8 to 1.4 wt % were solutionized, quenched, and then artificially aged (AA) at $180{}^{\circ }\mathrm{C}$, after which positron annihilation lifetime spectroscopy was applied to obtain information about precipitation and vacancy evolution during the preceding ageing step. Hardness and electrical resistivity measurements were carried out to complement these measurements. AA was carried out in four different heating media, which allowed for varying the average heating rate from 2.4 to $170\mathrm{K}{\mathrm{s}}^{-1}$. The main result of the study is that there is a competition between vacancy losses and precipitation. Any precipitation taking place during quenching or during heating to the AA temperature helps to prevent vacancies from going to sinks and allows them to assist in solute clustering. Higher solute content, slower heating to $180{}^{\circ }\mathrm{C}$, and natural preageing before AA were found to have a comparable effect.

中文翻译：

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Al-Mg-Si合金人工时效过程中空位和溶质簇的共同演化

将固溶物总含量为0.8至1.4 wt％的Al-Mg-Si合金固溶，淬火，然后在90℃下人工时效（AA） $180{}^{\circ }\mathrm{C}$之后，应用正电子an没寿命光谱来获取有关前一个老化步骤中的降水和空位演变的信息。进行硬度和电阻率测量以补充这些测量。AA在四种不同的加热介质中进行，这允许将平均加热速率从2.4更改为$170\mathrm{ķ}{\mathrm{s}}^{-\mathrm{1个}}$。该研究的主要结果是空缺与降水之间存在竞争。在淬火或加热至AA温度期间发生的任何沉淀物都有助于防止空位流向凹陷，并使它们有助于溶质聚集。溶质含量较高，加热速度较慢$180{}^{\circ }\mathrm{C}$，以及发现AA之前的自然预处理具有可比的效果。