B4C-TiB2-Al composites were fabricated by infiltrating aluminum into porous B4C-TiB2 preforms in vacuum. The microstucture and mechanical properties of the B4C-TiB2-Al composites were investigated. The hardness decreased, the flexural strength increased, and the fracture toughness first increased and then decreased slightly with an increase in TiB2 content. The BaC-TiB2-Al composite with 40wt.% TiB2 showed the optimized properties. The infiltrated aluminum addition was the leading reason for the fracture toughness improvement of the composites. The tear ridges and dimples on the fracture surface of the composites increased gradually with the increase of infdtrated alu- minum content showing inter/transgranular fracture mode. The relationships between the microstructures and the mechanical properties of the composites were discussed.
Lü Peng, YUE Xinyan, RU Hongqiang, and YU Liang Key Laboratory of the Ministry of Education for Anisotropy and Texture of Materials, Northeastern University, Shenyang 110004, China
