Understanding the Room Temperature Recovery Behavior in a Ti–24Nb–4Zr–8Sn Superelastic Alloy

Abstract

Metastable β Ti–Nb‐based superelastic alloys have potential uses in the biomedical and aerospace industries due to an attractive combination of properties. However, their mechanical response can be seen to vary with cycling, limiting their uptake. Furthermore, recent studies have also highlighted changes in properties under no applied stress at room temperature, with the reasons for these changes poorly understood. To investigate potential mechanisms for these changes, the superelastic behavior of Ti–2448 is studied during mechanical cycling both pre‐ and post‐room temperature (RT) aging treatments. On cycling, there is a reduction in both σSIM and hysteresis area, consistent with behavior commonly seen in the literature. However, during RT aging, there is a rapid, time‐dependent process leading to a partial recovery. In situ diffraction data indicated that this recovery is coincident with a reduction in internal stresses, the potential mechanisms for which are discussed.