A study on radiation effect of <200Â keV protons on M40J/epoxy composites

Irradiation of 160 keV protons was performed for the AG-80 epoxy resin and the unidirectional M40J/AG-80 composite, and changes in the bend strength, bend modulus, interlayer shear strength and mass loss ratio were examined. The variation of the chemical structure was characterized in terms of Dynamic Mechanical Thermal Analysis (DMA). Experimental results show that under the proton fluence lower than approximately 5.5 × 1015 cm−2, the cross-linking density increases with the fluence in the surface layer of the AG-80 epoxy matrix, leading to increasing the bend strength and modulus for the composite. With further increasing the fluence, the cross-linking density as well as the bend strength and bend modulus is decreased. The interlayer shear strength exhibits a similar trend as the bend strength and bend modulus to a certain extent. With the increase of proton fluence, the mass loss ratios for both the AG-80 epoxy resin and the M40J/AG-80 composites increase first and then level off.