初始多芯组合结构对NbTi/Cu超导线集束拉拔芯丝不均匀变形的影响  

Influence of initial multi-filamentary composite structure on inhomogeneous deformation of cored wires in NbTi/Cu superconducting wire during bundle-drawing

作　　者：刘君[1] 刘燕红 孙霞光 胡炽 唐文亭[1] LIU Jun;LIU Yan-hong;SUN Xia-guang;HU Chi;TANG Wen-ting(School of Materials Science&Engineering,Xi'an University of Technology,Xi'an 710048,China;National Engineering Laboratory for Superconducting Materials,Western Superconducting Technologies Co.,Ltd.,Xi'an 710018,China)

机构地区：[1]西安理工大学材料科学与工程学院,陕西西安710048 [2]西部超导材料科技股份有限公司超导材料国家工程实验室,陕西西安710018

出　　处：《塑性工程学报》2019年第6期191-198,共8页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(51605383);国家重点研发计划项目(2017YFE0301402);凝固技术国家重点实验室开放课题资助项目(SKLSP201641)

摘　　要：基于ABAQUS软件平台对NbTi/Cu多芯复合超导线集束拉拔过程进行有限元模拟,研究了多芯组合体坯料在集束拉拔过程中芯丝的不均匀变形规律及受力规律,分析了初始多芯组合结构对芯丝不均匀变形的影响。结果表明,在集束拉拔成形过程中,NbTi/Cu多芯组合体最外层芯丝变形后截面呈现不规则形状,中心芯丝及各内层芯丝截面形状趋于正六边形;由于多芯组合体边角轴上的位移约束作用显著,位于最外层边角位置的芯丝形状畸变程度最大,各内层芯丝中,位于边角轴部位的芯丝形状畸变程度要大于同层其他位置的芯丝,而优化初始多芯组合结构,能有效减小芯丝间的位移约束作用,改善芯丝的变形均匀性,提高复合超导线的临界电流密度值。The bundle-drawing process of NbTi/Cu multi-filamentary composite superconducting wire was numerically simulated by using ABAQUS.The laws of inhomogeneous deformation and loading of the cored wires in multi-filamentary composite during the bundle-drawing process were investigated,and the influence of the initial multi-filamentary composite structure on the inhomogeneous deformation of the cored wires was analyzed.The results show that during the bundle-drawing process,the cross-sections of cored wires in the outermost layer of formed NbTi/Cu multi-filamentary composite show irregular shapes,and the cross-sections of cored wires in the center and the middle layers of formed multi-filamentary composite tend to be regular hexagon.Since the displacement constraint is significant on the corners of the multi-filamentary composite,the cored wires in these positions of the outermost layer have the most severe shape distortion.For the middle layers,the shape distortion of cored wires on the corners is more serious than that on the other positions in the same layer.By optimizing the initial multi-filamentary composite structure,the displacement constraint between the cored wires can be reduced,the deformation uniformity of the cored wires can be improved,and the critical current density value of the composite superconducting wire can be increased.

关 键 词：多芯组合体 集束拉拔 不均匀变形 数值模拟 NbTi/Cu 

分 类 号：TB331[一般工业技术—材料科学与工程]