Abstract How to coordinate the strength, ductility and electrical conductivity of Cu-Cr-Zr alloys has always been a difficult problem. Unlike most of previous reports on processing soft state (solution state) alloys, in the present study, a hard state (aged state) Cu-Cr-Zr alloy was subjected to one-step friction stir processing (FSP) at room temperature with more attentions paid to the evolution of grains and precipitates, and their effects on the mechanical and electrical properties. The results showed that the precipitates played a key role in grain refinement, and ultrafine grains (UFG) with an average size of 250 nm were produced after FSP. Many fine precipitates (average size of 3.1 nm) were uniformly distributed in the grains, neither dissolved nor obviously coarsened. Excellent comprehensive properties of high tensile strength (702 MPa), good elongation (16%) and electrical conductivity (74.3% IACS) were achieved in the FSP sample. Furthermore, this one-step FSP method does not need subsequent aging treatment which is indispensable for conventional processing methods, providing a simplified and efficient method for improving the performance of Cu-Cr-Zr alloys.

中文翻译：

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通过一步搅拌摩擦加工优化硬态 Cu-Cr-Zr 合金的机械性能和电导率

摘要 如何协调Cu-Cr-Zr合金的强度、延展性和导电性一直是一个难题。与之前关于处理软态（固溶态）合金的大多数报告不同，在本研究中，硬态（时效态）Cu-Cr-Zr 合金在室温下进行一步摩擦搅拌处理 (FSP)关注晶粒和析出物的演化及其对机械和电学性能的影响。结果表明，析出物在晶粒细化中起关键作用，FSP后产生平均尺寸为250 nm的超细晶粒（UFG）。许多细小的析出物（平均尺寸为 3.1 nm）均匀分布在晶粒中，既没有溶解也没有明显的粗化。优异的综合性能高抗拉强度（702 MPa），在 FSP 样品中实现了良好的伸长率 (16%) 和电导率 (74.3% IACS)。此外，这种一步法 FSP 方法不需要传统加工方法必不可少的后续时效处理，为提高 Cu-Cr-Zr 合金的性能提供了一种简化而有效的方法。