Microstructure characterization of in situ Ti-TiB metal matrix composites prepared by powder metallurgy process

Metal matrix composites (MMCs) are the new generation materials that combine both the metallic properties (ductility and toughness) and ceramic characteristics (high strength and modulus), leading to higher strength in shear and compression at higher service temperatures. Titanium matrix composites possess light weight, high strength and good corrosion resistance and are used as structural materials in automobiles and aerospace industries. In the present study, in situ Ti-TiB composites were fabricated by reinforcing (2, 5, 10 and 20 wt. %) TiB2 powder into titanium matrix and subsequently consolidated by vacuum sintering at 1300oC for 3 h. X-ray diffraction and scanning electron microscopy (SEM) were carried out to characterize the prepared composites. The results showed that all compositions led to high density composites, and the hardness of the composites increased with an increase in the amount of reinforcement. The highest hardness achieved is 580 HV1 for Ti-20 wt. % TiB2 composites. The X-ray diffraction of the developed composites confirmed sucessful development of titanium in-situ TiB composites.