Quantitative characterization of microstructure of thermal deformed TA15 titanium alloy by EBSD

The microstructure of thermal deformed TA15 titanium alloy was quantitatively characterized by electron back-scattered diffraction (EBSD). The thermal compressive tests were carried out on Gleeble-1500 thermal simulator. The deforming temperature is from 750 degrees C to 950 degrees C, and the strain rate is from 10(-3)s(-1) to 1Is(-1). From EBSD data, not only gain size and phase volume fraction, but also grain boundary misorientation can be characterized. The results indicate that both alpha and beta grains were refined after thermal deformation. With deforming temperature increasing and strain rate decreasing, the fraction of high angle grain boundary and the volume fraction of beta phase increased. The variations of microstracture reflect the influence of deformation conditions on transformation dynamics and resrystallization.