高强高导铜铬锆合金晶体生长行为及电磁场调控机制

随着我国高铁网络的迅猛扩展及时速记录的不断刷新，对高铁接触线铜合金材料的结构强度与导电功能提出了越来越高的要求。高强高导铜铬锆合金是运行速度大于300km/h高速列车接触线的重要用材，接触线性能直接关系着高铁运行的安全。我们的前期研究结果表明施加电磁场可有效改善铜铬锆合金的凝固组织与力学性能，但由于原位分析手段的缺失，对电磁场调控的微观动力学机制缺乏足够的认知，这已成为制约工艺进一步发展的瓶颈。本项目依托我国大科学装置，应用高能同步辐射硬X射线原位成像与衍射技术，对电磁场调控下铜铬锆合金凝固过程中晶体的形核与生长、成分迁移、缺陷形成等进行实时成像与原位表征。系统研究电磁参数、凝固条件等对铜铬锆合金晶体生长行为的调控规律，深入理解电磁场调控铜铬锆合金凝固组织的动力学机制，为发展适合于工业应用的铜铬锆合金电磁连铸技术提供理论依据，满足高铁发展对结构功能一体化材料的需求。

High strenghth and high conductivity contact line is quite important for high way. Cu-Cr-Zr copper alloy is the key material for preparing the contact line in case of the speed over 350km/h. Our previous work indicated that electromagnetic field can effectively improve the structure and performance of Cu-Cr-Zr alloy. However, the modification mechanism especially the dynamics is still not clear due to the lack of in-situ testing method. In this project, the solidification behavior (grain growth, defect formation, solute transfer etc.) will be in-situ investigated by synchrotron radiation imaging and diffraction techniques. The effects of electromagnetic field and cooling conditions on solidification structure will be studied in detail. Thus, the dynamics mechanism of electromagnetic modification can be discovered, which is important for improving the electromagnetic continuous casting technology.