Investigation of curing characteristics of carbon fiber/epoxy composites cured with low-energy electron beam

To solve the penetration depth of carbon fiber/epoxy prepreg and irradiation dose uniformity by low-energy E-Beam under 125 keV, the both-side irradiation curing of prepreg was investigated. The results show that there is little thermal effect during the low-energy electron beam irradiation curing process, even though the irradiation dosage reached 300 kGy, only 46.2-C can be tested on the prepreg surface. Due to the low curing temperature, the degree of cure of prepreg was only 61.8% at 300 kGy level of irradiation, and the glass-transition temperature (T_g) was only 48.6-C. The degree of cure and T_g can be increased sharply by thermal postcure. After being postcured at 160-C for 30 min, the degree of cure and the T_g of prepreg reached 98.5% and 170.4-C, respectively. Interlaminar shear strength testing result indicate that the fabrication process of the composite layer by layer curing by the low- energy E-Beam is a promising cure approach.