As to the increasing demands for the light materials in weight-sensitive fields, scandium (Sc) is arguably known as one of the most attractive and effective microalloying elements to develop high-performance aluminum-based alloys applied at elevated temperature. This report exemplifies how the Sc microalloying effect can be fully utilized to seek for the synergetic stabilization between dual precipitates, more than simply forming the well-known Al₃Sc nanoprecipitates. Two sets of precipitation protocols are introduced to create a coexistence of θ′-Al₂Cu and Al₃Sc precipitates in an Al–Cu–Sc alloy, and the thermal stabilization of the two precipitates is found to be closely correlated. In the case of θ′-Al₂Cu precipitate decomposed because of an invalid protection from weak interfacial Sc segregation, the Al₃Sc precipitates will coarsen much quickly, which induces a simultaneous loss in thermal stability and strengthening effect of the dual precipitates. In contrast, a sensible approach is proposed to induce a strong Sc segregation at the θ′-Al₂Cu/matrix interface to greatly stabilizes the θ′-Al₂Cu precipitates even crept at 300°C and concomitantly suppresses the coarsening of Al₃Sc precipitates, leading to extremely high creep resistance. The acceleration effect of the Cu on the Al₃Sc coarsening is illustrated and can be alternatively prohibited by modified Sc partitioning to stabilized θ′-Al₂Cu precipitates as Cu storage and thus provides a much stronger coupling precipitate strengthening as well as creep resistance at elevated temperatures. This strategy is broadly applicable to other high-temperature alloy containing Sc together with primary elements such as Si, Mg, and Zn via the creation of precipitate co-stabilization.

关于重量敏感领域对轻质材料的日益增长的需求，scan（Sc）可以说是开发在高温下应用的高性能铝基合金的最有吸引力，最有效的微合金元素之一。该报告举例说明了如何充分利用Sc微合金化作用来寻求双重沉淀物之间的协同稳定作用，而不仅仅是简单地形成众所周知的Al ₃ Sc纳米沉淀物。引入两套沉淀协议来创建的共存θ' -Al ₂ Cu和Al ₃中的Al-Cu-钪合金，并且两个析出物的热稳定化钪沉淀被发现密切相关。在的情况下，θ' -Al由于对弱界面Sc偏析的保护无效而使₂ Cu析出物分解，Al ₃ Sc析出物将迅速粗化，同时引起热稳定性的丧失和双重析出物的强化作用。与此相反，明智的做法是提出以诱导在强烈钪离析θ' -Al ₂的Cu /基质界面以大大稳定了θ' -Al ₂ Cu析出甚至悄悄在300℃并同时抑制Al的粗大化₃ Sc沉淀，导致极高的抗蠕变性。Cu对Al ₃的加速作用示出了Sc粗化，并且可以通过修改Sc分配作为稳定的θ'-Al ₂ Cu沉淀物（作为Cu储存）来替代，从而阻止Sc粗化，从而在高温下提供更强的偶联沉淀强度以及抗蠕变性。这种策略可广泛地适用于其他含有Sc和主要元素（例如Si，Mg和Zn）的Sc，通过产生沉淀物共同稳定化，可以将其与其他高温合金一起使用。