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Title: Engineered Ceramic Insulators for High Field Magnets

Abstract

High field magnet coils made from brittle A15 superconductors need to be rigidly contained by their support structure but yet be electrically insulated from it. Current insulators (end shoes, pole pieces, spacers, mandrels, etc.) are often made from coated metallic shapes that satisfy the mechanical and thermal requirements but are electrically unreliable. The insulating coating on the metal core too often chips or flakes, causing electrical shorts. Any replacement insulator materials must manage the thermal expansion mismatch to control the stress within the coil enabling the achievement of ultimate magnet performance.A novel ceramic insulator has been developed that eliminates the potential for shorting while maintaining high structural integrity and thermal performance. The insulator composition can be engineered to provide a thermal expansion that matches the coil expansion, minimizing detrimental stress on the superconductor. These ceramic insulators are capable of surviving high temperature heat treatments and are radiation resistant. The material can withstand high mechanical loads generated during magnet operation. These more robust insulators will lower the magnet production costs, which will help enable future devices to be constructed within budgetary restrictions.

Authors:
 [1]
  1. MultiPhase Composites, LLC, Longmont, CO, 80501 (United States)
Publication Date:
OSTI Identifier:
20800173
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 824; Journal Issue: 1; Conference: Cryogenic engineering conference, Keystone, CO (United States), 29 Aug - 2 Sep 2005; Other Information: DOI: 10.1063/1.2192363; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE; CERAMICS; CONTROL; HEAT TREATMENTS; MAGNET COILS; METALS; OPERATION; PERFORMANCE; SPACERS; STRESSES; SUPERCONDUCTING MAGNETS; SUPERCONDUCTORS; SUPPORTS; THERMAL EXPANSION

Citation Formats

Rice, J. A. Engineered Ceramic Insulators for High Field Magnets. United States: N. p., 2006. Web. doi:10.1063/1.2192363.
Rice, J. A. Engineered Ceramic Insulators for High Field Magnets. United States. doi:10.1063/1.2192363.
Rice, J. A. Fri . "Engineered Ceramic Insulators for High Field Magnets". United States. doi:10.1063/1.2192363.
@article{osti_20800173,
title = {Engineered Ceramic Insulators for High Field Magnets},
author = {Rice, J. A.},
abstractNote = {High field magnet coils made from brittle A15 superconductors need to be rigidly contained by their support structure but yet be electrically insulated from it. Current insulators (end shoes, pole pieces, spacers, mandrels, etc.) are often made from coated metallic shapes that satisfy the mechanical and thermal requirements but are electrically unreliable. The insulating coating on the metal core too often chips or flakes, causing electrical shorts. Any replacement insulator materials must manage the thermal expansion mismatch to control the stress within the coil enabling the achievement of ultimate magnet performance.A novel ceramic insulator has been developed that eliminates the potential for shorting while maintaining high structural integrity and thermal performance. The insulator composition can be engineered to provide a thermal expansion that matches the coil expansion, minimizing detrimental stress on the superconductor. These ceramic insulators are capable of surviving high temperature heat treatments and are radiation resistant. The material can withstand high mechanical loads generated during magnet operation. These more robust insulators will lower the magnet production costs, which will help enable future devices to be constructed within budgetary restrictions.},
doi = {10.1063/1.2192363},
journal = {AIP Conference Proceedings},
number = 1,
volume = 824,
place = {United States},
year = {Fri Mar 31 00:00:00 EST 2006},
month = {Fri Mar 31 00:00:00 EST 2006}
}
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