Abstract In the Al–Mg system, intermetallic compounds can be formed by a solid-state reaction between the elemental components. Metal matrix composites obtained by classical powder metallurgy and room temperature extrusion with the two compositions Al60–Mg40 and Al40–Mg60 (wt. %) were studied. The high fraction of Al–Mg grain boundaries in these materials allows investigation of the early stages of phase evolution. The mixtures are close to the ideal composition of either the intermetallic β-Al3Mg2 phase or the γ-Al12Mg17 phase. Phase analysis was performed using intense synchrotron radiation with an energy of 87 keV and showed that the γ-Al12Mg17 phase was the first to form after 2 h annealing at 200 °C. In situ annealing at 200 °C for 12 h and at 250 °C for 6 h was compared to ex situ annealing at 200 °C and 250 °C for 2 h and 12 h. The γ-phase was the first phase to form, independent of the starting composition. It is suggested that the γ-phase grows via an interface reaction controlled mechanism. After the γ-phase has reached its critical thickness the β-phase starts to form. No other phases were observed to form.

中文翻译：

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Al-Mg 金属基复合材料在 200 °C 和 250 °C 低温退火过程中的相演变

摘要 在 Al-Mg 体系中，金属间化合物可以通过元素组分之间的固态反应形成。研究了通过经典粉末冶金和室温挤压获得的具有两种成分 Al60-Mg40 和 Al40-Mg60（重量百分比）的金属基复合材料。这些材料中高比例的 Al-Mg 晶界允许研究相演化的早期阶段。混合物接近金属间 β-Al3Mg2 相或 γ-Al12Mg17 相的理想组成。使用能量为 87 keV 的强同步辐射进行相分析，结果表明 γ-Al12Mg17 相在 200°C 下退火 2 小时后首先形成。将在 200 °C 下原位退火 12 小时和在 250 °C 下保持 6 小时与在 200 °C 和 250 °C 下原位退火 2 小时和 12 小时进行比较。γ 相是第一个形成的相，与起始成分无关。这表明 γ 相通过界面反应控制机制生长。在 γ 相达到其临界厚度后，β 相开始形成。没有观察到形成其他相。