We demonstrate a strategy to stabilize nanoprecipitates in Al–Cu alloys, based on computational design that identifies synergistic solutes (Sc and Fe) that simultaneously segregate to the θ′-Al₂Cu/Al interface and strongly bond to one another. Furthermore, Sc and Fe are predicted to each segregate into a separate atomic plane, forming a sandwiched structure reinforcing the interface. This interfacial architecture was realized through a simple heat treatment in a Sc–Fe–Si triple-microalloyed Al–Cu model alloy. Such a back-to-back layered interface, thermodynamically stable and kinetically robust, is found to suffocate nanoprecipitate coarsening at 300°C, enabling a dramatic reduction in creep rate.

IMPACT STATEMENT

The segregant architecture of synergistic solute at θ′-Al₂Cu/Al interface was guided by computational calculations and artificially realized at atomic scale to achieve an ultra-high thermal stability of θ′-Al₂Cu, leading to a high creep resistance at 300°C.

我们展示了一个策略中的Al-Cu合金中以稳定纳米沉淀物，基于计算的设计，标识协同溶质（SC和Fe）中同时分离到θ' -Al ₂铜/铝界面，并强烈粘结到彼此。此外，预计Sc和Fe各自偏析成一个单独的原子平面，形成加强界面的夹心结构。这种界面结构是通过在Sc-Fe-Si三微合金Al-Cu模型合金中进行简单的热处理而实现的。发现这种背对背的分层界面具有热力学稳定性和动力学鲁棒性，可在300°C的温度下使纳米沉淀粗化窒息，从而显着降低蠕变速率。

影响陈述

协同溶质在该偏析架构θ' -Al ₂铜/铝界面用计算机计算引导并且在原子尺度人为实现来实现的超高热稳定性θ' -Al ₂的Cu，导致高的抗蠕变性在300℃。