Low temperature flow behavior of B2 intermetallic phase in Ti-Al-Nb system

Low temperature flow behavior of polycrystalline B2 intermetallic in Ti-Al-Nb system has been studied in a range of temperature (77-298 K) and strain rate (10−4 to 10−3 s−1). To assess the rate limiting mechanisms, activation volume and energy have been determined. Relatively low values of activation volume (20-50b3) and activation energy (0.2μb3) suggest that a short-range obstacle that is Peierls barrier restricts the dislocation movement. Work hardening behavior of the intermetallic is also studied and contrasted with that of other B2 intermetallics. The intermetallic exhibits extremely low rates of work hardening that is attributed to localized and planar flow.