M. Ozerov

Wear resistance of Ti/TiB composites produced by spark plasma sintering

The tribological characteristics of Ti/TiB composites were studied in as-sintered condition and after isothermal multiaxial forging. A mixture of commercially pure Ti and TiB2 powders was used to produce Ti/TiB composites with 8.5 and 17 vol % of TiB via in-situ Ti+TiB2→Ti+TiB reactions during spark plasma sintering at 1000°C. During isothermal multiaxial forging (MAF), the material was exposed to successive compressions along three orthogonal directions at a temperature of 700°C and strain rate of 10–3 s−1 to cumulative strains e = 5.2. The microstructure of the as-sintered composites consisted of TiB whiskers nonuniformly distributed within the Ti matrix. In the forged composites, intensive shortening of TiB whiskers occurred. The hardness of the composites increased greatly compared to that of commercially pure Ti; the hardness also increased with increasing the TiB fraction. The hardness in the forged composites decreased by ∼20% for both composite states. Tribological tests using a standard ball-on-d...

Kinetics of Microstructure Refinement in Titanium Alloys during Deformation

The effect of various factors on the kinetics of microstructure evolution in commercial-purity titanium and two-phase Ti-6Al-4V alloy during deformation was studied. The kinetics of microstructure refinement can be raised via intensification of deformation twinning. In two-phase titanium alloys the kinetics of spheroidization can be increased considerably by decrease in the thickness of initial α lamellae. The influence of interphase boundaries energy on deformation behavior was discussed with respect to Ti-6Al-4V and Ti/TiB alloys.