▎ 摘　　要

Boron carbide (B4C) hybrids with different contents of graphene oxide (GO) were prepared by a heterogeneous co-precipitation method using cetyltrimethyl ammonium bromide (CTAB) as the cationic surfactant. The asobtained mixtures were further hot-pressed at 1950 degrees C for 60 min under 30 MPa, by which B4C-reduced GO (rGO) composites were fabricated. It was found that the addition of only 0.5 wt% rGO could alter the predominance of trans-granular fracture in monolithic B4C ceramic material to mixed trans-granular and intergranular modes in B4C-rGO composites. The flexural strength and fracture toughness of the B4C-2 wt% rGO were increased by 31% (from 350 to 455 MPa) and 83% (from 3.20 to 5.85 MPa.m(1/2)), respectively, compared with those of pure B4C. The improved mechanical properties are attributed to the mechanisms of pull-out and bridging of rGO and crack deflection, as evidenced by microstructural observations. The energy dissipation in the present B4C-rGO composites was further verified using two micromechanical models.