Abstract The solution experiments on cold rolled 2024 Al sheet with a 1070 Al coating were carried out at various temperatures and holding time. The effects of solution parameters on the microstructure evolution and mechanical properties were studied. The results showed that the alloying elements diffused from the 2024 Al matrix to the 1070 Al coating, following the peak-valley pattern. The cold rolled 2024 Al sheet mainly have the second phases of Al2Cu, S (Al2CuMg), Si, Mg2Si, and the impurities of AlFeMnSi, AlCuFeMnSi, AlCuFeMn, and the amount of them was reduced with increasing solution temperature or holding time. T (Al20Cu2Mn3) had precipitated before aging, and only the Cu–Mg clusters were formed during the natural aging, which should be the main strengthening mechanism. The grain structure was elongated during cold rolling, while the static recrystallization and grain growth occurred during the solution treatment. The ultimate tensile strength, yield strength and elongation were gradually enhanced with increasing the solution temperature to 510 °C. When the solution temperature is further increased to 530 °C, the elongation was obviously decreased due to the over-burning. Moreover, it was found that the solution temperature had much stronger effects on the mechanical properties than that of the holding time.

中文翻译：

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固溶处理对自然时效 EN AW 2024 铝合金薄板组织和力学性能的影响

摘要 在不同温度和保温时间下对具有 1070 Al 涂层的冷轧 2024 Al 薄板进行固溶实验。研究了溶液参数对显微组织演变和力学性能的影响。结果表明，合金元素从 2024 Al 基体扩散到 1070 Al 涂层，遵循峰谷模式。冷轧2024铝板主要有第二相Al2Cu、S(Al2CuMg)、Si、Mg2Si和AlFeMnSi、AlCuFeMnSi、AlCuFeMn等杂质，其含量随固溶温度或保温时间的增加而减少。T(Al20Cu2Mn3)在时效前已经析出，自然时效过程中只形成了Cu-Mg团簇，这应该是主要的强化机制。冷轧时晶粒结构被拉长，而固溶处理过程中发生静态再结晶和晶粒长大。随着固溶温度升高到510℃，极限抗拉强度、屈服强度和伸长率逐渐提高。当固溶温度进一步升高到530℃时，由于过度燃烧，延伸率明显下降。此外，发现固溶温度对机械性能的影响比保温时间强得多。