Beta grain growth behaviour of TG6 and Ti17 titanium alloys

The grain growth kinetics of TG6 and Ti17 alloys in the β phase have been studied. The grain size parameters have been obtained by means of the image analysis software for different heat treatment temperatures and times. The growth time exponents and activation energies have also been determined. The activation energies for grain growth of both alloys increase with the increase in soaking time. This trend might be due to the different solute drag effect. The uniformity of grain size under each heat treatment has also been studied and the variations resulted from the combined action of nucleation rate of β phase and β grain growth velocity.

► Growth exponents were 0.35–0.38 for TG6 alloy and 0.27–0.30 for Ti17 alloy.
► The growth time exponents of both the alloys increased with increasing temperature.
► The activation energy for grain growth increased with increasing the soaking time.
► Increasing solute drag effect resulted in the increasing activation energies.
► Combined action of nucleation and growth of β grain decided grain size uniformity.