Creep and the anomalous yield stress of Ni3Ga

Ni3Ga single crystals with [−123] and [001] orientations have been tested for creep across the temperature range of the yield stress anomaly. At the [001] axial orientation, the creep rate increases with time, exhibiting so-called `inverseʹ creep, until the peak temperature of the yield stress above which steady-state creep takes place. `Inverseʹ creep involves slipping on {111} planes. At the [−123] axial orientation, steady-state creep is observed over the entire temperature range investigated. The creep strength shows a normal decrease with temperature and the active slip system is 〈100〉{001}.