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Title: Gas Evolution Measurements on Reactor Irradiated Advanced Fusion Magnet Insulation Systems

Abstract

Glass-fiber reinforced plastics (GFRPs) are used as insulation materials for the superconducting magnet coils of the International Thermonuclear Experimental Reactor (ITER). The radiation environment present at the magnet location will lead to gas production, swelling and weight loss of the laminate, which may result in a pressure rise combined with undefined stresses on the magnet coil casing. Consequently, these effects are important parameters for the engineering and design criteria of superconducting magnet coil structures. In this study, newly developed epoxy and cyanate-ester (CE) based S2-glass fiber reinforced insulation systems were irradiated at ambient temperature in the TRIGA-Mark II reactor (Vienna) to a fast neutron fluence of 1 and 5x1021 m-2 (E>0.1 MeV) prior to measurements of gas evolution, swelling and weight loss. The CE based laminates show increased radiation resistance, i.e. less gas evolution. The highest radiation hardness up to the highest dose was observed in a pure CE system. In addition, the effects of swelling and weight loss are either negligible or less pronounced for all systems. The results prove that the newly developed CE based composites are serious candidate insulation systems for ITER.

Authors:
; ;  [1]; ; ;  [2]
  1. Atomic Institute of the Austrian Universities, 1020 Wien (Austria)
  2. Composite Technology Development, Inc., Lafayette, CO (United States)
Publication Date:
OSTI Identifier:
20800177
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: 10.1063/1.2192369; (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; AMBIENT TEMPERATURE; DOSES; EPOXIDES; ESTERS; FAST NEUTRONS; FIBERGLASS; HARDNESS; IRRADIATION; ITER TOKAMAK; MAGNET COILS; PHYSICAL RADIATION EFFECTS; REINFORCED PLASTICS; STRESSES; SUPERCONDUCTING MAGNETS; SWELLING; TRIGA-2 REACTOR

Citation Formats

Humer, K., Seidl, E., Weber, H. W., Fabian, P. E., Feucht, S. W., and Munshi, N. A. Gas Evolution Measurements on Reactor Irradiated Advanced Fusion Magnet Insulation Systems. United States: N. p., 2006. Web. doi:10.1063/1.2192369.
Humer, K., Seidl, E., Weber, H. W., Fabian, P. E., Feucht, S. W., & Munshi, N. A. Gas Evolution Measurements on Reactor Irradiated Advanced Fusion Magnet Insulation Systems. United States. doi:10.1063/1.2192369.
Humer, K., Seidl, E., Weber, H. W., Fabian, P. E., Feucht, S. W., and Munshi, N. A. Fri . "Gas Evolution Measurements on Reactor Irradiated Advanced Fusion Magnet Insulation Systems". United States. doi:10.1063/1.2192369.
@article{osti_20800177,
title = {Gas Evolution Measurements on Reactor Irradiated Advanced Fusion Magnet Insulation Systems},
author = {Humer, K. and Seidl, E. and Weber, H. W. and Fabian, P. E. and Feucht, S. W. and Munshi, N. A.},
abstractNote = {Glass-fiber reinforced plastics (GFRPs) are used as insulation materials for the superconducting magnet coils of the International Thermonuclear Experimental Reactor (ITER). The radiation environment present at the magnet location will lead to gas production, swelling and weight loss of the laminate, which may result in a pressure rise combined with undefined stresses on the magnet coil casing. Consequently, these effects are important parameters for the engineering and design criteria of superconducting magnet coil structures. In this study, newly developed epoxy and cyanate-ester (CE) based S2-glass fiber reinforced insulation systems were irradiated at ambient temperature in the TRIGA-Mark II reactor (Vienna) to a fast neutron fluence of 1 and 5x1021 m-2 (E>0.1 MeV) prior to measurements of gas evolution, swelling and weight loss. The CE based laminates show increased radiation resistance, i.e. less gas evolution. The highest radiation hardness up to the highest dose was observed in a pure CE system. In addition, the effects of swelling and weight loss are either negligible or less pronounced for all systems. The results prove that the newly developed CE based composites are serious candidate insulation systems for ITER.},
doi = {10.1063/1.2192369},
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}
}
  • Advanced composite materials reinforced with boron-free glass fibers are candidate insulation materials for fusion magnets, in particular for ITER. Thus, these systems require an excellent performance and mechanical integrity after irradiation. The present innovative organic insulation system consists of R-glass fiber reinforced tapes impregnated with an advanced cyanate-ester/epoxy resin. This composite is suitable for vacuum-pressure impregnation. In order to assess the radiation resistance of the mechanical properties, the laminate was irradiated in the TRIGA reactor (Vienna) to the ITER design fluence level of 1x1022 m-2 (E>0.1 MeV). The blend was screened at 77 K using the static tensile and short-beam-shearmore » test prior to and after irradiation. In addition, tension-tension fatigue measurements were done in order to investigate the material performance under pulsed operating conditions.« less
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  • In a Tokamak fusion reactor device like ITER, insulation materials for superconducting magnets are usually fabricated by a vacuum pressure impregnation (VPI) process. Thus these insulation materials must exhibit low viscosity, long working life as well as good radiation resistance. Previous studies have indicated that cyanate ester (CE) blended with epoxy has an excellent resistance against neutron irradiation which is expected to be a candidate insulation material for a fusion magnet. In this work, the rheological behavior of a CE/epoxy (CE/EP) blend containing 40% CE was investigated with non-isothermal and isothermal viscosity experiments. Furthermore, the cryogenic mechanical and electrical propertiesmore » of the composite were evaluated in terms of interlaminar shear strength and electrical breakdown strength. The results showed that CE/epoxy blend had a very low viscosity and an exceptionally long processing life of about 4 days at 60 °C.« less