New Design of Bismuth Borate Ceramic/Epoxy Composites with Excellent Fracture Toughness and Radiation Shielding Capabilities

In the present work, ceramic/epoxy composites consisting of bismuth borate reticulated porous ceramics cross-linked with epoxy resin were prepared. The ceramic skeleton was prepared using the polymer replication method and exhibited a synergistic neutron/gamma shielding capability while also being able to disperse the phase. Additionally, the increased boric acid content in the slurry promotes the growth of pores on the surface of the ceramic skeleton and increases its roughness, which directly affects the bonding of the ceramic to the epoxy resin. The phase composition, microstructure, and physical properties of the ceramic skeleton, as well as the interfacial bonding, fracture mechanisms, and neutron/gamma shielding capabilities of the composites, are systematically described. The shielding rates of the prepared composites against neutrons and gamma rays were 67.3% and 16.82%, respectively. The bulk density and fracture toughness reached 2.22 g/cm3 and 54.64 MPa·m1/2, respectively. Our preparation process and analytical methods offer new opportunities for the effective design of flexible radiation shielding material for nuclear reactors.