Microstructure Tracking of Ti‐6Al‐4V by In‐Situ Synchrotron Diffraction During Thermomechanical Process in Beta Field

Kurzfassung

The deformation mechanism of the α+β alloys is still controversially reported in the literature as either discontinuous dynamic recrystallization or dynamic recovery. This work analyses systematically the evolution of the microstructure of Ti-6Al-4V during and after deformation above the β-transus temperature by in-situ synchrotron diffraction to determine separately static and dynamic restoration mechanisms. Hot compression is carried out in the β field up to true strain of 0.6 and strain rates between 0.001 and 5s-1, followed by heat Treatment up to 5 minutes at the same temperature. The evolution of the Debye-Scherrer rings are analyzed to study the crystallographic behavior of individual grains and this information is correlated by microscopy. The deformation results in subgrains formation, denoting dynamic recovery as the main mechanism of restoration followed by continuous dynamic recrystallization. Static recrystallization observed after deformation and its high rate, could be the reason of misinterpretation of the dynamic restoration mechanisms.