采用气雾化-冷等静压-热挤出工艺制备 Al-Mn-Mg-Sc-Zr 合金，并研究其室温至 300 ℃范围内的高温拉伸性能及多尺度析出相演化规律。 结果表明，热挤出态合金形成细小等轴晶组织，基体中弥散分布微米级 Al6Mn 相和纳米级 Al3(Sc, Zr)析出相，同时在晶界处存在不连续分布的 MgO 颗粒。 室温下，合金抗拉强度和屈服强度分别为 460.3 MPa和 422.8 MPa， 伸长 率 为 3.9%； 当温 度 升 至 200 ℃时获 得 较 优 强 塑 匹 配 ， 其抗 拉 强 度 、 屈服 强 度 和 伸 长 率 分 别 为219.8 MPa、200.2 MPa 和 23.8%。 组织分析表明，高温条件下 Al6Mn 相发生明显粗化，析出强化作用减弱；而具有 L12 有序结构并与 α-Al 基体保持共格界面的 Al3(Sc, Zr)相因 Sc 和 Zr 扩散速率较低，仍具有较高热稳定性并持续提供强化作用。 同时，晶界处存在少量不连续分布的 MgO 颗粒。 多尺度析出相热稳定性的差异是调控该合金高温拉伸行为的主导因素。

Al-Mn-Mg-Sc-Zr alloys were fabricated by gas atomization, cold isostatic pressing, and hot extrusion, and their high-temperature tensile properties and multiscale precipitate evolution from room temperature to 300 ℃ were investigated. The as-extruded alloy has a fine equiaxed grain structure with micron-sized Al6Mn particles and nanoscale Al3(Sc, Zr) precipitates dispersed in the matrix, whereas discontinuously distributed MgO particles are present along the grain boundaries. At room temperature, the strength of the alloy is high, with an ultimate tensile strength of 460.3 MPa and a yield strength of 422.8 MPa, but the elongation is limited to 3.9%. At 200 ℃,a favourable strength-ductility balance is obtained, with an ultimate tensile strength of 219.8 MPa, a yield strength of 200.2 MPa, and an elongation of 23.8% . Microstructural analysis indicates that the Al6Mn phase coarsens significantly at elevated temperatures, leading to a weakened strengthening effect. In contrast, the nanoscale Al3(Sc, Zr) precipitates with an ordered L12 structure maintain coherent interfaces with the α-Al matrix and exhibit excellent thermal stability because of the sluggish diffusion of Sc and Zr, thereby continuously contributing to strengthening. Moreover, a small amount of discontinuously distributed MgO particles is present at the grain boundaries. The elevated-temperature tensile behavior of the alloy is governed primarily by the distinct thermal stability of multiscale precipitates.