Elevated Temperature Mechanical Behavior of Severely Deformed Titanium

In this investigation, compression tests were performed at a strain rate of 0.001-0.1 s(-1) in the range of 600-900 degrees C to study the high temperature deformation behavior and flow stress model of commercial purity (CP) titanium after severe plastic deformation (SPD). It was observed that SPD via equal channel angular extrusion can considerably enhance the flow strength of CP titanium deformed at 600 and 700 degrees C. Post-compression microstructures showed that, a fine grained structure can be retained at a deformation temperature of 600 degrees C. Based on the kinematics of dynamic recovery and recrystallization, the flow stress constitutive equations were established. The validity of the model was demonstrated with reasonable agreement by comparing the experimental data with the numerical results. The error values were less than 5% at all deformation temperatures except 600 degrees C.