基于有限元方法的超导线协调变形研究进展

Research Progress on Coordinated Deformation of Superconducting Wires Based on Finite Element Method

摘要:

NbTi、Nb₃Sn、MgB₂、Bi系超导材料的结构复杂，金属间、金属与粉体间及芯丝间的协调变形均匀性决定了线材加工质量和力学性能。线材和模具结构、加工工艺、变形条件是影响其协调变形行为的重要因素，基于有限元数值模拟方法，分析和评估多种因素下超导线材的协调变形行为是一种重要工程手段，能够较为准确和直观地分析多层、多芯复合结构超导线材成形过程协调流变行为及复合相间及其界面处的应力/应变分配。本综述旨在概述超导线材成形过程有限元模拟的研究进展，归纳总结了超导线材成形有限元模型构建、本构模型选择及边界条件设置等。同时论述了变形参数、模具结构和加工工艺对协调变形行为影响机制及多尺度分析最新研究进展。

Abstract:

The structures of NbTi, Nb₃Sn, MgB₂, and Bi-based superconducting materials are complex. The uniformity of coordinated deformation among metals, between metals and powders, and within core wires determines the processing quality and mechanical properties of wires. The structures of wires and dies, processing parameters, and deformation conditions are important factors affecting their coordinated deformation behavior. The finite element numerical simulation method is an important engineering tool for analyzing and evaluating the coordinated deformation behavior of superconducting wires under multiple factors. This approach can accurately and intuitively simulate the coordinated rheological behavior during the forming process of multi-layer and multifilament composite superconducting wires, as well as the stress/strain distribution among composite phases and their interfaces. This review summarizes recent progress in finite element simulation of superconducting wire forming. It covers the establishment of finite element models, selection of constitutive models, and setting of boundary conditions for superconducting wire forming. At the same time, the review discusses the affecting mechanism of deformation parameters, die structure, and processing technique on coordinated deformation behavior, as well as recent advances in multi-scale analysis.