FABRICATION AND CHARACTERIZATION OF TiB AND TiC REINFORCED Ti-5Al-5Mo-5V-1Cr-1Fe TITANIUM MATRIX COMPOSITE

摘要

Ti-5Al-5Mo-5V-1Fe-1Cr titanium matrix composites (TMCs) with different volume fractions of trace TiB and TiC were fabricated via in situ synthesis method. The synergistic effect of TiB and TiC reinforcements on microstructure and tensile properties of TMCs were evaluated. The tensile properties were greatly improved due to the formation of TiB and TiC reinforcements, and the reinforcements also significantly refined the microstructure. Transmission electron microscope (TEM) examinations showed that the increasing of reinforcements could promote the spheroidization of α phase. The separated α phase, near equiaxed α phase and short-rod α phase tended to be spheroidized during the diffusion process. Then the microstructural homogeneity was improved. The results showed that the synergistic effect of TiB and TiC significantly affected the refinement of microstructure and the improvement of tensile properties. A proper weight fraction of TUB and TiC would provide the composite with better properties.