Reactive hot pressing and mechanical properties of B4C/Li2O–Al2O3–SiO2 composites

•B4C/LAS composites have been fabricated by hot pressing method.•The addition of B4C is beneficial for consolidation of LAS matrix.•The reaction mechanism between B4C and LAS matrix is presented.

B4C/Li2O–Al2O3–SiO2 (B4C/LAS) composites with different B4C contents were fabricated using hot-pressing technique. Mechanical properties of the B4C/LAS composites were investigated as a function of initial B4C content. The addition of B4C deteriorated both fracture toughness and flexural strength of the composites initially. B4C/LAS composites demonstrated improved mechanical properties when initial B4C content increased to 10 wt.%. XPS, XRD and TEM analyses illustrated that a chemical reaction took place between B4C and LAS matrix. The synergism of high relative density, high crystallinity and fine grain size, was responsible for improved mechanical properties of B4C/LAS composites.