Fabrication and tensile properties of in situ TiBw and TiCp hybrid-reinforced titanium matrix composites based on Ti-B4C-C

To evaluate the synergistic effect of TiB whisker (TiBw) and TiC particle (TiCp) on tensile properties of titanium matrix composites (TMCs), 10 vol.% TiBw and TiCp reinforced TMCs with TiBw/TiCp volume ratios of 4:1, 2:1, 1:1, 1:2, and 1:4 were prepared by reactive hot processing of Ti-B4C-C. The tensile strength and modulus of the TMCs were greatly improved due to the formation of TiBw and TiCp. The composite with the ratio of 1:1 possessed the best tensile properties among the composites. Fractography showed that all the composites possess a brittle cleavage fracture mode at room-temperature, and TiCp can prevent cracks from being formed more effectively than TiBw. The results show that the synergistic effect of TiBw and TiCp significantly affects the tensile properties of TMCs, and a proper volume ratio of TiBw to TiCp would provide the composite with better properties. (c) 2007 Elsevier B.V. All rights reserved.