A novel neutron shielding AA6061/B4C laminar composite fabricated by powder metallurgy:SPS-HER

In this study, novel-structured (Type A and Type B) laminar A6061/B4C neutron absorber composites were designed and fabricated using spark plasma sintering followed by hot extrusion and rolling (SPS-HER). It was found that B4C particles were evenly distributed in the fabricated composites. The interfaces between particle/matrix and different layers were bonded well. After hot rolling, regions containing large orientation gradient and high dislocation density were found near the B4C particles, which helped dynamic recrystallization (DRX) and grain refinement in the composite. Compared with that of the asextruded AA6061/B4C laminar composite, yield and ultimate tensile strengths of the as-rolled AA6061/B4C laminar composite are clearly improved. Two yield points were noticed in the material during the tensile test. The composite containing high B4C particle content was found easy to fracture and the fracture mode was ductile. (C) 2019 Elsevier B.V. All rights reserved.