Abstract By combining differential scanning calorimetry analysis and high-resolution transmission electron microscopy observations, the precipitation map for Al–Cu–Mg alloy (AA2024-T3) is obtained for a wide temperature range from 85 to 250 °C and ageing durations from 1 to 10,000 h. For the first time, the appearance of equilibrium S–Al2CuMg phase is observed at 85 °C from 1000 h of ageing. Hardness values superposed with the precipitation map reveal that the maximum hardness for all studied temperatures is located at the frontier between S-phase + Guinier-Preston-Bagaryatski (GPB) zones and S-phase regions.

中文翻译：

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Al-Cu-Mg合金（AA2024-T3）的沉淀硬度图

摘要 结合差示扫描量热分析和高分辨透射电子显微镜观察，获得了 Al-Cu-Mg 合金（AA2024-T3）的析出图，温度范围为 85 至 250 °C，时效持续时间为 1 至10,000 小时。从 1000 小时时效开始，在 85 °C 下首次观察到平衡 S-Al2CuMg 相的出现。与沉淀图叠加的硬度值表明，所有研究温度的最大硬度位于 S 相 + Guinier-Preston-Bagaryatski (GPB) 区和 S 相区域之间的边界。