Dislocation properties were studied in several L12 Ni-based alloys with high (Ni74Al26), medium (Ni3(Al, 0.25%Hf)), and low (Ni3Ga) antiphase boundary energies respectively, deformed in the temperature domain of the yield-stress anomaly. Several antiphase boundary energies were measured and compared with those found in the literature. The peak in the temperature variation of the strain-hardening coefficient was correlated with the unlocking of incomplete Kear-Wilsdorf locks. The corresponding unlocking stresses, as well as the frequencies of octahedral-cube and cube-octahedral cross-slip, were strongly correlated with the respective fault energies. The local pinning of near-edge dislocations in cube planes appears essential for the observation of the yield-stress anomaly in alloys with high antiphase boundary energies.

Comparison of Ni-Based Alloys with Extreme Values of Antiphase Boundary Energies - Dislocation Mechanisms and Mechanical Properties. Conforto, E., Molénat, G., Caillard, D.: Philosophical Magazine, 2005, 85[2-3], 117-37