铜铬系合金因其优异机械和导电性能，是新一代超薄集成电路引线框架和时速385km以上高速铁路接触网线的关键用材。传统铜铬二元合金抗软化能力不足，添加锆可提高其耐热性，但锆易氧化且与结晶器内衬反应，导致其添加困难且分布不均使得合金组织成分和性能难控。发展新型无锆的高强高导抗软化铜铬系合金成分与结构优化设计理论、方法已成为研究的重点。项目团队预研发现通过控制Mg、Si元素的添加可大幅提高铜铬合金的抗软化性能。本项目拟研究Mg、Si协同作用对Cu-Cr合金时效析出行为及组织性能演变的影响规律，结合合金中原子团簇特征及升温过程中结构演变模拟计算，揭示合金时效析出特征，从原子尺度阐明合金抗高温软化机理，形成高强高导抗软化Cu-Cr-Mg-Si合金组织调控技术原型，为发展高强高导抗软化铜铬系合金设计理论、开发新型高性能铜铬系合金提供理论和技术支撑。

Because of its excellent mechanical and electrical conductivity, Cu-Cr-based alloys are the ideal candidate materials for next generation ultra-thin integrated circuit lead frames and contacting lines of high-speed railway with speeds of over 380 km/h. Traditional Cu-Cr binary alloys have relative low strength and poor softening resistance performance at elevated temperature, while the microstructure and properties of Cu-Cr-Zr alloys are difficult to control because Zr is easy to oxidize and reacts with the inner lining of the mould. The current researches have been focusing on the development of design theory, methodology and characteristic mechanism for new Zr-free Cu-Cr-system alloys with high strength, high conductivity and excellent anti-softening properties. According to our previous studies, the strength, conductivity and softening resistance performance of the Cu-Cr alloy can be greatly improved by controlling the addition of Mg and Si elements. This project intends to study the synergistic effect of Mg and Si on the aging precipitation behavior and the evolution of microstructure and properties of Cu-Cr alloys. Combined with the characteristics of atomic clusters in alloys and the simulation calculation of structural evolution during heating process, the aging precipitation characteristics, transformation sequence and the mechanism of softening resistance performance at elevated temperature of alloys will be revealed. A prototype of structure control technology for Cu-Cr-Mg-Si alloys with high strength, high conductivity and softening resistance will be established. All these could provide theoretical and technical support for the development of design theory of Cu-Cr-system alloy and the development of copper-chromium alloys with high strength, high conductivity and excellent softening resistance performance.