Structure and mechanical properties of an Ni3Al single crystal upon high-temperature deformation

Structure and strength properties of single-crystal 〈001〉 samples of Ni 3 Al have been studied in the as-grown and homogenized state during tensile tests in the temperature range of 1150–1250°C. At the strain rate of 1.32 mm/min (2 × 10 −5 m/s), the samples are in the state of superplasticity. The basic mechanism of relaxation is dynamic recovery; in some regions of the sample, recrystallized grains are formed. At 1250°C, coarse twins are observed in the zone of fracture, which indicates the “switching on” of additional slip systems necessary to guarantee the relaxation process.