Characterization of Microstructure and Texture Evolution in Ti664 Titanium Alloy After Multidirectional Forging and Annealing Treatments

Abstract

In previous investigations, it was demonstrated that texturing of the microstructure in titanium alloy inevitably occurs after forging in one direction. In this work, the influence of multidirectional forging and annealing on the heterogeneity of the microstructure and crystallographic orientation of a new α + β titanium alloy (Ti-6Al-6Mo-4V) has been studied. A heterogeneous orientation distribution and morphology was observed in the microstructure, containing matrix β grains and α lamellae elongated along the deformation direction after multidirectional forging. Meanwhile, significant //axial direction (AD) and //AD textures were formed because of the special deformation mode. After annealing at 825°C, a more homogeneous microstructure was obtained, but the annealing had a limited effect on the texture components. The same texture components were found because of the texture inheritance effect, and the variation of the texture intensity contributed to the grain dissolution and recrystallization effect during subsequent annealing.