REACTOR IRRADIATION EFFECTS ON THE ULTIMATE TENSILE AND THE INTERLAMINAR SHEAR-STRENGTH OF CARBON-FIBER-REINFORCED EPOXIES AT 77 K

A carbon fibre reinforced plastics material (CFRP) 'TORAYCA T300 3K', which was developed for various applications, including cryogenics, wa s irradiated at 5 K and 340 K with different reactor spectra up to a f ast neutron fluence of 5 x 10(22) m(-2) (E > 0.1 MeV). All investigati ons in the interlaminar shear mode as well as the tensile tests were m ade at 77 K, the samples subjected to 5 K irradiation were measured be fore and after an annealing cycle (of about one day) to room temperatu re. Fractographic examinations of the tensile samples were used to exa mine the complicated fracture process. Both the interlaminar shear str ength and the ultimate tensile strength show good radiation resistance at the lowest total absorbed dose (similar to 5 x 10(6) Gy), but fail at higher dose levels (similar to 10(8) Gy). (C) 1998 Elsevier Scienc e Ltd. All rights reserved.