Superconducting joints using reacted multifilament MgB_(2)wires:A technology toward cryogen-free MRI magnets  

作　　者：Dipak Patel Akiyoshi Matsumoto Hiroaki Kumakura Yuka Hara Toru Hara Minoru Maeda Hao Liang Yusuke Yamauchi Seyong Choi Jung Ho Kim Md Shahriar A.Hossain 

机构地区：[1]School of Mechanical and Mining Engineering,The University of Queensland,St Lucia,Queensland 4072,Australia [2]National Institute for Materials Science(NIMS),1-2-1 Sengen,Tsukuba,Ibaraki 305-0047,Japan [3]Department of Electrical Engineering and Kangwon High Magnetic Field Center,Institute of Quantum Convergence Technology,Kangwon National University,Gangwon 24341,Republic of Korea [4]Australian Institute for Bioengineering and Nanotechnology(AIBN),The University of Queensland,St Lucia,Queensland 4072,Australia [5]Department of Materials Process Engineering,Graduate School of Engineering,Nagoya University,Nagoya,Aichi 464-8603,Japan [6]Institute for Superconducting and Electronic Materials,Australian Institute for Innovative Materials,University of Wollongong,North Wollongong,New South Wales 2500,Australia

出　　处：《Journal of Magnesium and Alloys》2024年第1期159-170,共12页镁合金学报（英文）

基　　金：the Japan Society for the Promotion of Science(JSPS)KAKENHI Grant Number JP18F18714;Cryogenic Station,Research Network and Facility Services Division,National Institute for Materials Science(NIMS),Japan;supported by the ARC Linkage Project(LP200200689)。

摘　　要：The development of superconducting joining technology for reacted magnesium diboride(MgB_(2))conductors remains a critical challenge for the advancement of cryogen-free MgB_(2)-based magnets for magnetic resonance imaging(MRI).Herein,the fabrication of superconducting joints using reacted carbon-doped multifilament MgB_(2)wires for MRI magnets is reported.To achieve successful superconducting joints,the powder-in-mold method was employed,which involved tuning the filament protection mechanism,the powder compaction pressure,and the heat treatment condition.The fabricated joints demonstrated clear superconducting-to-normal transitions in self-field,with effective magnetic field screening up to 0.5 T at 20 K.To evaluate the interface between one of the MgB_(2)filaments and the MgB_(2)bulk within the joint,serial sectioning was conducted for the first time in this type of superconducting joint.The serial sectioning revealed space formation at the interface,potentially caused by the volume shrinkage associated with the MgB_(2)formation or the combined effect of the volume shrinkage and the different thermal expansion coefficients of the MgB_(2)bulk,the filament,the mold,and the sealing material.These findings are expected to be pivotal in developing MgB_(2)superconducting joining technology for MRI magnet applications through interface engineering.

关 键 词：Mg B2 superconducting joint MgB_(2)conductor MRI applications Cryogen-free magnet Persistent-mode operation 

分 类 号：TH77[机械工程—仪器科学与技术] TQ132.2[机械工程—精密仪器及机械]