力学反作用下Nb_(3)Sn高场超导线圈磁-热不稳定性研究现状和挑战  

Research status and challenges related to thermal-magnetic instability of niobium-tin high-field superconducting coils

作　　者：薛存 贾鹏 汪庆渝 任晗熹 胡帅 曹凯威 雍华东 XUE Cun;JIA Peng;WANG Qing-Yu;REN Han-Xi;HU Shuai;CAO Kai-Wei;YONG Hua-Dong(School of Mechanics,Civil Engineering and Architecture,Northwestern Polytechnical University,Xi’an 710072,China;School of Aeronautics,Northwestern Polytechnical University,Xi’an 710072,China;College of Civil Engineering and Mechanics,Lanzhou University,Lanzhou 730000,China)

机构地区：[1]西北工业大学力学与土木建筑学院,西安710072 [2]西北工业大学航空学院,西安710072 [3]兰州大学土木工程与力学学院,兰州730000

出　　处：《中国科学：物理学、力学、天文学》2024年第11期55-84,共30页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家自然科学基金(编号:12372210);中央高校基本科研业务费(编号:lzujbky-2024-jdzx02)资助项目。

摘　　要：Nb_(3)Sn线圈是高场磁体的关键核心部件,在高能物理、先进医疗、磁约束核聚变等方面有重要应用.然而国内外在Nb_(3)Sn高场磁体制备后的测试过程中,遇到大量磁通跳跃,导致超导载流能力急速下降,严重影响失超保护,容易诱发过早失超.另外,超导线圈在强磁场、大电流环境下发生明显力学变形,而且超导电磁性能对力学变形很敏感,所以力学应变下Nb_(3)Sn线圈磁-热不稳定性成为研制高场超导磁体亟待解决的难题之一.在造价高昂和后期很难修补和改造的背景下,发展Nb_(3)Sn超导线圈磁-热不稳定性数值模拟方法,揭示电磁力对磁通跳跃和失超的影响机制,对抑制超导线圈磁通跳跃的优化设计和加快高场Nb_(3)Sn磁体研制进度有重要意义.本文回顾了Nb_(3)Sn高场磁体应用中涉及的力-电-磁-热多场耦合问题的研究现状,梳理了Nb_(3)Sn超导线圈在应用中涉及的复杂本构关系、超导线圈磁-热稳定性和力学反作用这三个亟待解决的关键科学问题,并探讨了其中的困难和挑战.Niobium-tin,or Nb_(3)Sn,coils are the key components of high-field magnets and have important applications in highenergy physics,advanced medical treatment,magnetic constraint nuclear fusion,and other fields.However,after the preparation of niobium-tin high-field magnets,many flux jumps are encountered during the testing process.These jumps cause the superconducting current-carrying capacity to drop rapidly,affecting quench protection and inducing premature quenching.In addition,the superconducting coils undergo significant mechanical deformation in a strong magnetic field and high current environment.The superconducting electromagnetic performance is sensitive to mechanical deformation.Therefore,magnetic-thermal instability of niobium-tin coils during the development of high-field superconducting magnets is an urgent problem to be solved.Development of numerical simulation methods for resolving magneticthermal instability of niobium-tin superconducting coils,as well as revealing the influence mechanism of electromagnetic forces on flux jumps and quenching,is of great significance.As the earlier methods were difficult and costly,the optimization design development for inhibiting the flux jump of superconducting coils will help accelerate the development of high-field Nb_(3)Sn magnets.This article reviews the research status of the multi-field coupling problems related to force-electric-magnetic-thermal involved in Nb_(3)Sn high-field magnet applications;shares the solutions to three key scientific problems in the application of Nb_(3)Sn superconducting coils,namely complex constitutive relations,magnetic-thermal stability,and mechanical reaction;and discusses the difficulties and challenges involved.

关 键 词：超导力学 Nb_(3)Sn高场磁体 临界电流 磁-热不稳定 力学反作用 

分 类 号：O511.3[一般工业技术—材料科学与工程]