基于电磁复合的难互溶钢/铅界面非平衡冶金结合机理及性能调控研究

核工业的发展对钢/铅层状复合材料提出了长寿命服役的新要求，其难以通过胶粘、钎焊等间接连接方式实现，然而熔点差异大、难互溶的钢/铅难以通过常规工艺直接冶金结合。受到铁铅在高能球磨撞击非平衡状态下产生高度化合混合相的启发，本项目巧妙地提出利用电磁复合成形方法的瞬时局部高速冲击实现钢/铅界面高温高压非平衡态直接冶金结合的新思路，并通过初步研究验证了其可行性。然而钢/铅电磁复合界面非平衡冶金组织形成机理尚不明确，界面整体复合性能有待进一步提高，因此本项目拟系统研究钢/铅电磁复合过程弹塑性变形规律、钢铅冲击接触界面材料变形机制以及非平衡状态下界面冶金结合层形成机理，以实现对钢铅界面结合性能的调控。该研究的开展将有利于满足核工业对长寿命新型钢/铅层状复合材料的重要需求，也对其它难互溶金属体系复合材料的成形提供借鉴，具有重要的工程应用价值和科学意义。

With the development of nuclear industry, steel/lead laminated composite is required to have much longer service life, which is difficult to be satisfied by indirect bonding method, such as adhesive bonding and Brazing. However, the significant melting point difference and extreme poor miscibility between steel and lead result that they are difficult to be directly metallurgical bonded by conventional processes. Inspired by the appearance of iron-rich Pb/Fe phases with high degree of chemical disorder under the non-equilibrium state produced by high-energy ball milling, we propose a new idea that creating the non-equilibrium state with high temperature and high pressure in steel/lead interface by taking advantage of the high-speed local impact process during electromagnetic forming, which could lead to the direct metallurgical bonding of steel/lead. And its feasibility was verified through preliminary research. However, the formation mechanism of the non-equilibrium metallurgical microstructure in the bonding interface of steel/lead has not been clarified, and the interfacial mechanical performance of overall composite tube also needs to be further improved. Therefore, we intend to systematically study the elastic-plastic deformation mechanism of the steel/lead during electromagnetic forming process, the micro deformation mechanism of the steel/lead in the impacting interface and the formation mechanism of the interface metallurgical bonding layer under the non-equilibrium state, so as to improve the steel/lead interface bonding performance. The research will be helpful to meet the important requirement of nuclear industry for new long serve life steel/lead laminated composite, and also will provide reference for the preparation of other immiscible bi-metallic composites, which has great practical and scientific significance.