Modified Epoxy Resin Systems as Composite Insulation in Fusion Confinement Systems
DOE Phase I Contract DE-FG02-05ER84183
Superconducting magnet coils are a major component of plasma fusion experimental devices. The electrical insulation in these magnet coils is a polymer matrix composite, which must exhibit good mechanical strength and radiation resistance at cryogenic temperatures. The resin must also be suitable for vacuum pressure impregnation of these very large magnet coils. A major problem is the release of gases by the organic material during irradiation. Current resin systems do not combine good processing characteristics with mechanical strength and radiation resistance.
The program will begin with preparation of silsesquioxane-epoxy resins, which will be thermally cross-linked to generate end use materials. The formulation will be systematically optimized to enhance processing properties (viscosity and pot-life), radiation resistance and cryogenic mechanical strength. In Phase II the optimized formulation will be fully characterized in terms of mechanical and electrical properties, and radiation induced degradation and outgassing.
The effects of silsesquioxane upon epoxy radiation resistance as measured by gas evolution experiments after irradiation will be performed. Short beam shear, flexural and through thickness compressive strength will be determined for glass fiber reinforced silsesquioxane-epoxy composite specimens. These results will be compared to a pure epoxy formulation in order to determine if performance goals have been achieved.
Applications of the resin systems include electrical insulation for cryogenic superconducting magnet systems, particularly those which will be subjected to irradiation. This high performance resin system will be of interest for cryogenic and high-temperature composite structural applications, which are fabricated by liquid impregnation methods such as Resin Transfer Molding. Other potential applications for these materials exist in areas such as automotive components and parts, aerospace equipment, industrial belts and hoses and other applications where high-temperature resistance and weatherability are required.