On the influence of processing parameters on microstructural evolution of a near alpha titanium alloy

The effect of processing parameters on the microstructural evolution of Ti60 alloy were examined by isothermal compression tests over the temperature range of 960-1110 degrees C at constant strain rates of 0.001-10 s(-1). It was found that the flow stress decreased with increasing temperature and decreasing strain rate. The flow stress behavior revealed greater flow softening in the alpha + beta phase field compared with that of beta phase field. The volume fraction and grain size of primary alpha phase decreased and the prior-beta grain size increased with increasing temperature. The lamellar alpha phase within the prior-beta grains were distorted, broken up and globularized in the alpha + beta phase field, while a small amount of recrystallized grains were formed at the elongated prior-beta grain boundaries in the beta phase field. The degree of dynamic recrystallization increased with increasing temperature, strain rate and strain. The recrystallized grain size increased with increasing temperature and decreasing strain rate. (C) 2011 Elsevier B.V. All rights