Influence of reactor irradiation on the mechanical behavior of ITER TF coil candidate insulation systems

Extensive material tests have to be performed in order to obtain information on the radiation induced change in the mechanical behavior of insulating materials for the ITER Toroidal Field (TF) coil. The investigated insulation systems are R-glass fiber reinforced tapes, vacuum impregnated with a DGEBA epoxy resin and interleafed with Kapton H-foils. According to the actual operating conditions of ITER–FEAT, the systems were irradiated in the TRIGA reactor (Vienna, Austria) to neutron fluences of 5×1021 and 1×1022 m−2 (E>0.1 MeV). Static tensile, short-beam-shear (SBS) as well as double-lap-shear (DLS) tests were carried out at 77 K prior to and after irradiation. Furthermore, results on swelling and weight loss as well as on the material properties under tension–tension fatigue loading conditions are presented.