超导多芯圆线复杂微结构对其宏观力-电-热耦合特性的影响

超导多芯圆线通常是以超导Bi2Sr2CaCu2Ox(简称Bi2212)为主以银为基体采用粉末管制法制备而成的多芯纤维复合圆线结构。因其优异的导电性能及力学相关特性的各向同性，使得在强电、高场领域凸显不可替代的竞争优势。近来，材料微结构分析发现，热处理之后的超导多芯圆线内部结构非常复杂：超导相向银基体中生长，使得纤维表面呈现极不规则的几何构造，部分甚至与邻近纤维搭接。为此，本项目将从复杂微结构分析出发，以微观结构决定其宏观特性为主线，通过构建既能准确抓住微观几何构造的主要特征，又能有效地研究对其宏观特性影响的理论模型，综合运用理论分析、实验验证与数值计算相结合的手段，着重针对与提升超导多芯圆线"导电能力和载流运行稳定性"密切相关的基础性课题-复杂微结构对其基本力学行为和电-热稳定特性的影响-展开研究，探求其宏观特性对复杂微结构的本质关联，给出影响规律，为材料制备和相关工程设计提供理论依据。

Superconducting Bi2Sr2CaCu2Ox (Bi2212) multi filamentary composite round wires (RWs) are fabricated by the OPIT (Oxide Powder In Tube) to be a composite structure with the Bi2212 filament embedded silver matrix. Due to the distinct superconductivity and physical isotropy, it has an irreplaceable competitive feature in the applications of high magnetic field, especially for superconducting magnet. Most recently, the microstructure analysis found that the microstructure of the Bi2212 is very complicated. Specifically, the surface of the Bi2212 filament is very irregular and jagged. Thus, in this project, from the data of the microstructure analysis, we will construct the rational and effective theoretic model. On this bases, the effect of the microstructure of the Bi2212 multi filamentary RWs on its macro properties of mechanical, electric and thermal coupling will be comprehensively studied. This investigation of the correlation between the microstructure and macro properties is believed to be helpful to the fabrication of the Bi2212 RWs and its relative technical safety design.