Effect of Plastic Deformation on the Structure and Properties of the Ti/TiB Composite Produced by Spark Plasma Sintering

Resumo

A Ti/17 vol % TiB composite material is produced by spark plasma sintering of a mixture of titanium and 10 wt % TiB₂ powders at a temperature of 1000°C. Multiaxial isothermal forging is performed at t = 850°C to enhance the mechanical properties of the composite. Deformation develops dynamic recrystallization in the titanium matrix and shortens TiB whisker crystals by a factor of ~3. Multiaxial isothermal deformation decreases the temperature of the brittle-to-ductile transition of the Ti/TiB composite material by ~200°C (from ~500 to ~300°C) and results in a plasticity of ~5% upon compression at room temperature. Deformation decreases the microhardness and the wear resistance to a certain degree. Multiaxial isothermal deformation weakly changes the corrosion properties of the composite material in comparison with the initial state.