The Effect of Charge Component Composition on the Structure and Properties of Titanium Matrix Sintered Composites with High-Modulus Compounds

The effect of the powder matrix base (Ti and TiH2) and the type of reinforcing additives (5 wt.% TiC, TiB2, B, and B4C) on the structurization features and some properties of metallic matrix composites sintered hereof is investigated. It is shown that the application of titanium hydride powder with TiC and TiB2 additives as the starting powder base allows obtaining sintered materials with lower porosity (≤2%) and higher hardness, compared to the composites produced based on commercial titanium powder. The microstructure of sintered composites considerably depends on the type of reinforcing additives. TiC particles hardly interact with the matrix phase and they are relatively equilibrium, while the TiB inclusions (as it is in the case of TiB2 additive) are acicular 1–5 μm in dia. and 10–25 μm long. The microstructure of the composites sintered from the mixture of titanium hydride and boron carbide powders has conglomerates 20–50 μm in size, consisting of highly dispersed acicular particles of titanium boride phases and unimportant number of TiC equilibrium particles.