A combination of computational and experimental weak-beam transmission electron microscopic dislocation imaging was used to distinguish between the dislocation core models that had been proposed, for the [011] super-dislocation, on the basis of energy hierarchies. These preliminary computational results suggested that the hierarchy of planar fault energies in Ti-54at%Al was:

ECSF > EAPB > ESISF = ESESF

where CSF was the complex stacking fault, APB was the antiphase boundary, SISF was the self-interstitial stacking fault and SESF was the superlattice extrinsic stacking fault. The value of the antiphase boundary energy was expected to be greater than 250mJ/m2, whereas the self-interstitial stacking fault energy appeared to be 140mJ/m2. This was comparable to the superlattice extrinsic stacking fault energy of 142mJ/m2.

J.M.K.Wiezorek, C.J.Humphreys: Scripta Metallurgica et Materialia, 1995, 33[3], 451-8