Fabrication of ultra-fine grained and dispersion-strengthened titanium materials by spark plasma sintering

Titanium materials with high strength and hardness at room temperature have been developed by introducing very fine Ti5Si3 dispersoids into an ultra-fine grained titanium matrix. After high-energy ball milling of a Ti–Si powder mixture SPS (spark plasma sintering) was used to consolidate the granules. For both process steps, an optimization of the parameters was necessary. XRD, SEM and TEM were used to investigate the mechanism of formation of Ti5Si3 dispersoids during SPS at various sintering temperatures and sintering times and furthermore, to characterize the microstructure with regards to titanium matrix grain size, dispersoid size and dispersoid distribution. The new material shows high hardness, strength and improved wear resistance in comparison to other titanium materials.