Anisotropic antiphase boundaries in rapidly solidified Ni₃Al

Rapid solidification of Ni₃Al produces a network of curved antiphase boundaries (APB). Annealing, which allows a closer to equilibrium structure to develop, results in the APBs preferentially aligned on {100} planes; thus indicating that the APB energy is less on {100} planes than on other planes. This provides the first direct experimental evidence of an APB energy anisotropy which forms the basis of the Kear-Wilsdorf cross slip model used to explain the increase in yield stress with an increase in temperature. © 1985.