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Title: Effects of Rutherford Cable Parameters on Nb3Sn Extracted Strand Deformation and Performance

Abstract

In order to optimize parameters for Rutherford cables used in accelerator magnets, a number of cables were fabricated with different keystone angles, packing factors and numbers of strands. The effect of these parameters was measured on Nb{sub 3}Sn strand performance and deformation for two different RRP designs. High and low field current carrying capabilities and RRR were measured for the extracted strands. To correlate strand deformation with performance, the former was measured for several cables and conditions as a function of the strand location in the cable cross section.

Authors:
; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
950876
Report Number(s):
FERMILAB-PUB-08-623-TD
Journal ID: ISSN 1051-8223; TRN: US0902072
DOE Contract Number:
AC02-07CH11359
Resource Type:
Journal Article
Resource Relation:
Journal Name: IEEE Trans.Appl.Supercond.18:1114-1117,2008; Journal Volume: 18; Journal Issue: 2
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; ACCELERATORS; CABLES; CROSS SECTIONS; DEFORMATION; MAGNETS; PERFORMANCE; Accelerators

Citation Formats

Turrioni, Daniele, Barzi, Emanuela, Bossert, M., Collings, E.W., Nazareth, V., Sumptions, M.D., Yamada, R., Zlobin, A.V., and /Fermilab. Effects of Rutherford Cable Parameters on Nb3Sn Extracted Strand Deformation and Performance. United States: N. p., 2008. Web. doi:10.1109/TASC.2008.922386.
Turrioni, Daniele, Barzi, Emanuela, Bossert, M., Collings, E.W., Nazareth, V., Sumptions, M.D., Yamada, R., Zlobin, A.V., & /Fermilab. Effects of Rutherford Cable Parameters on Nb3Sn Extracted Strand Deformation and Performance. United States. doi:10.1109/TASC.2008.922386.
Turrioni, Daniele, Barzi, Emanuela, Bossert, M., Collings, E.W., Nazareth, V., Sumptions, M.D., Yamada, R., Zlobin, A.V., and /Fermilab. 2008. "Effects of Rutherford Cable Parameters on Nb3Sn Extracted Strand Deformation and Performance". United States. doi:10.1109/TASC.2008.922386.
@article{osti_950876,
title = {Effects of Rutherford Cable Parameters on Nb3Sn Extracted Strand Deformation and Performance},
author = {Turrioni, Daniele and Barzi, Emanuela and Bossert, M. and Collings, E.W. and Nazareth, V. and Sumptions, M.D. and Yamada, R. and Zlobin, A.V. and /Fermilab},
abstractNote = {In order to optimize parameters for Rutherford cables used in accelerator magnets, a number of cables were fabricated with different keystone angles, packing factors and numbers of strands. The effect of these parameters was measured on Nb{sub 3}Sn strand performance and deformation for two different RRP designs. High and low field current carrying capabilities and RRR were measured for the extracted strands. To correlate strand deformation with performance, the former was measured for several cables and conditions as a function of the strand location in the cable cross section.},
doi = {10.1109/TASC.2008.922386},
journal = {IEEE Trans.Appl.Supercond.18:1114-1117,2008},
number = 2,
volume = 18,
place = {United States},
year = 2008,
month = 6
}
  • Knowledge of the three-dimensional strain state induced in the superconducting filaments due to loads on Rutherford cables is essential to analyze the performance of Nb{sub 3}Sn magnets. Due to the large range of length scales involved, we develop a hierarchical computational scheme that includes models at both the cable and strand levels. At the Rutherford cable level, where the strands are treated as a homogeneous medium, a three-dimensional computational model is developed to determine the deformed shape of the cable that can subsequently be used to determine the strain state under specified loading conditions, which may be of thermal, magnetic,more » and mechanical origins. The results can then be transferred to the model at the strand/macro-filament level for rod restack process (RRP) strands, where the geometric details of the strand are included. This hierarchical scheme can be used to estimate the three-dimensional strain state in the conductor as well as to determine the effective properties of the strands and cables from the properties of individual components. Examples of the modeling results obtained for the orthotropic mechanical properties of the Rutherford cables are presented.« less
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