Improved mechanical properties in titanium matrix composites: Controllable TiBw distribution by thermal deformation process

Abstract

Due to the increasing demand for aerospace structural components, the need for strength-plasticity matching materials has become more urgent. The development of titanium matrix composites (TMCs) has provided new ideas to address the issue. In this work, we prepared TMCs by spark plasma sintering (SPS) with Ti-6Al-4 V (TC4) and TiB2 as the matrix and reinforcement, respectively. The TiB whisker (TiBw) generated by the in-suit reaction between the matrix and TiB2 results in grain size refinement of α-Ti, local strains, and additional dislocations in the composites, which enhance the mechanical properties. To further optimize the tensile properties, the sintered composites underwent hot rolling, inducing grain fragmentation and ordered arrangement of reinforcement, thus preventing dislocation movement and improving the bearing effect. In addition, we investigated the effect of rolling reduction on the arrangement direction of TiBw and quantified the strength increase attributed to its directional arrangement. We have achieved TMCs with the ultimate strength of 1440 MPa while maintaining good elongation up to 7.3%. This work may promote the design and applications of TMCs.