抄録
Several organic insulators in superconducting magnets for fusion reactors are irradiated in a fission reactor at 5K and their mechanical properties are measured at liquid nitrogen temperature (77K).
After irradiation with fast neutron fluence of 1.7×1017 nvt and γ dose of 4.5×108R, polypropylene is broken into pieces and polycarbonate and Mylar becomes too brittle to permit tensile test. Breaking stress and elongation of Nomex reduce as compared with that of unirradiated specimen. Kapton exhibits only a little decrease in breaking stress after irradiation of fast neutron fluence of 3.3×1017nvt and γ dose of 8.8×108R, and shows the most excellent properties against the irradiation.
