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 degrees 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 degrees C. The degree of cure and T-g can be increased sharply by thermal postcure. After being postcured at 160 degrees C for 30 min, the degree of cure and the T-g of prepreg reached 98.5% and 170.4 degrees 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. POLYM. COMPOS., 36:1731-1737, 2015. (c) 2014 Society of Plastics Engineers