Reinforcement of neutron shielding composites with three-dimensionally interwoven structures via reticulated porous ceramic skeletons

摘要

In this study, neutron shielding composites (NSC) with an interpenetrating network structure are prepared with epoxy resin, B_4C particles, and reinforced by different pore sizes reticulated porous ceramic skeletons (RPCS). The bonding strength between B_4C particles and epoxy resin is improved via the surface modified process. The viscosity of B4C/epoxy resin is decreased with the increase in temperature. As increasing the curing temperature, the time to reach the gelation point decreases. After reaching the gelation point, the composite viscosity of B_4C/ epoxy resin is increased sharply. Because of adding the RPCS, flexural strength and thermal conductivity of the NSC specimens are increased, while the thermal expansion coefficient is progressively decreased. Compared with the specimen without RPCS, the flexure strength and thermal conductivity of the NSC specimen 30 PPI (pores per inch) are increased by 129.27 and 756, but the thermal expansion coefficient is reduced by 81.66. Under the same thickness, the NSC specimens from 10 PPI to 30 PPI, the sub-cadmium neutron (E < 0.4 eV) shielding capacity is increased first and then decreased. The NSC specimen 15 PPI has the best sub-cadmium neutron shielding capacity, the sub-cadmium neutron shielding capacity reaches 80.67 (0.5 cm).