Constitutive Model and Processing Maps for a Ti‐55511 Alloy in β Region

Abstract

The flow behavior of a high‐strength Ti alloy (Ti‐55511) in the β region is studied by hot compressive experiments. A dislocation density–based constitutive equation, together with processing maps, is established to describe the flow behavior and hot workability of the studied Ti alloy. It is found that the strain rate () and temperature ( T ) distinctly influence the hot compressive deformation behavior. The flow stress increases distinctly with a rising or reducing T . The main softening mechanism in the β region is dynamic recovery (DRV). The established constitutive equation based on the work hardening (WH) and DRV mechanisms has the desired prediction accuracy, and the correlation coefficient between the predicted and experimental results is 0.9912. The processing maps indicate that a high strain rate (0.4–10 s −1 ) easily causes unstable deformation, whereas low and medium strain rates (0.001–0.2 s −1 ) are suitable for hot compressive deformation of the studied alloy.