Low temperature neutron and gamma irradiation of glass fiber reinforced epoxies

Measurements of the fracture strength of epoxies, which are reinforced with different types of fiber glass and used commercially for magnet insulation are described. The samples were exposed to reactor irradiation at 77 K, and measurements of tensile strength in the direction of the fibers were taken at the same temperature without warm up. The results show moderate degradation of the fracture strength up to a total dose of 7.4x107 Gy, a linear swelling by about 5% at the same dose and a total destruction of the composite after a dose of proportional 1.5x108 Gy. (orig.)