ABSTRACT Alloying of Fe, Co was reported to tailor microstructure of copper alloys into a nanoprecipitate-fine grain (NPFG) structure, i.e. nano-sized iron-rich precipitates dispersed inside refined grains. Here, we investigate the solute effect of Sn, Zn on NPFG structure in as-cast copper samples. Mechanisms are proposed to account for the solute effect on precipitate and grain features. Solutes restrict coarsening but facilitate undesirable morphology transition from spherical to angular of iron-rich precipitates. Meantime, solutes allow more precipitates to be active in the nucleation of copper and consequently induce finer grains. Minor Sn is added to optimise NPFG structure and leads to an excellent strength–ductility combination in Cu–1.5Fe–0.1Sn (wt-%) alloy. This work provides a solute-alloying strategy to achieve desired mechanical properties in metals. GRAPHICAL ABSTRACT

中文翻译：

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溶质含量对纳米析出物-细晶协同增强铜合金显微组织的影响

摘要 据报道，铁、钴的合金化可将铜合金的微观结构调整为纳米沉淀-细晶粒 (NPFG) 结构，即纳米尺寸的富铁沉淀分散在细晶粒内。在这里，我们研究了 Sn、Zn 对铸态铜样品中 NPFG 结构的溶质影响。提出了解释溶质对沉淀物和晶粒特征的影响的机制。溶质限制粗化但促进富铁沉淀物从球形到角形的不希望的形态转变。同时，溶质允许更多的沉淀物在铜的成核中活跃，从而导致更细的晶粒。添加少量 Sn 以优化 NPFG 结构，并在 Cu-1.5Fe-0.1Sn (wt-%) 合金中产生出色的强度-延展性组合。这项工作提供了一种溶质合金化策略，以在金属中实现所需的机械性能。图形概要