Tensile Fracture of TiB Whisker Reinforced Ti Alloy Matrix Composites

TiB whisker reinforced Ti alloy matrix (Ti-TiB) composites have attracted attention as the aerospace materials with their high specific mechanical properties for long time. However, strengthening mechanism of Ti-TiB composites has not been revealed because of the agglomeration and incomplete precipitation of TiB whiskers in the Ti alloy matrix yet. In this study, we addressed to fabricate fully-dense TiB whisker reinforced Ti-6Al-4V alloy matrix (Ti6Al4V-TiB) composites via powder metallurgical process, which have the microstructure to discuss their tensile properties with the theories for composite materials. The Young's modulus and ultimate tensile strength of Ti6Al4V-10 vol% TiB composite were 130 GPa and 1193 MPa, respectively. Note that the elongation of Ti6Al4V-10 vol% TiB composite was approximately 2.8 % although the elongations of Ti-TiB composite have been reported are few (; less than 1%) due to the agglomeration of TiB whiskers in Ti matrix.