Materials, Strands, and Cables for Superconducting Accelerator Magnets. Final Report

Sumption, Mike D.¹  Collings, Edward W.¹ 

[1] Ohio State University, Columbia, OH (United States)

关键词: Superconducting cables;    superconducting strands;    magnetization;    Nb3Sn;    YBCO;    Bi:2212;    MgB2;   

DOI  :  10.2172/1157029
RP-ID  :  DOE-OSU--95ER40900-final
PID  :  OSTI ID: 1157029

学科分类：核物理和高能物理

美国|英语

来源: SciTech Connect

【 摘 要 】

This report focuses on Materials, Strands and Cables for High Energy Physics Particle accelerators. In the materials area, work has included studies of basic reactions, diffusion, transformations, and phase assemblage of Nb₃Sn. These materials science aspects have been married to results, in the form of flux pinning, B_c2, B_irr, and transport J_c, with an emphasis on obtaining the needed J_c for HEP needs. Attention has also been paid to the ???intermediate-temperature superconductor???, magnesium diboride emphasis being placed on (i) irreversibility field enhancement, (ii) critical current density and flux pinning, and (iii) connectivity. We also report on studies of Bi-2212. The second area of the program has been in the area of ???Strands??? in which, aside from the materials aspect of the conductor, its physical properties and their influence on performance have been studied. Much of this work has been in the area of magnetization estimation and flux jump calculation and control. One of the areas of this work was strand instabilities in high-performance Nb₃Sn conductors due to combined fields and currents. Additionally, we investigated quench and thermal propagation in YBCO coated conductors at low temperatures and high fields. The last section, ???Cables???, focussed on interstrand contact resistance, ICR, it origins, control, and implications. Following on from earlier work in NbTi, the present work in Nb₃Sn has aimed to make ICR intermediate between the two extremes of too little contact (no current sharing) and too much (large and unacceptable magnetization and associated beam de-focussing). Interstrand contact and current sharing measurements are being made on YBCO based Roebel cables using transport current methods. Finally, quench was investigated for YBCO cables and the magnets wound from them, presently with a focus on 50 T solenoids for muon collider applications.