The energies of unrelaxed antiphase boundaries, straight after formation, were calculated for the B2 and D03 structures by using numerical results which arose from the irregular tetrahedron approximation of the cluster variation method. The latter took account of first- and second-nearest neighbor interactions. The cases of a<100>(001), a<100>(01¯1) and a<1¯1¯1>(01¯1) were treated. Numerical results which were obtained for the body-centered cubic Fe-Al system at 1000 and 623K showed that the antiphase boundary energies for the first 2 cases were negligibly small; except for the stability region of the D03 phase at 623K. Use of the tetrahedron approximation made it possible to reveal clearly the effect of short-range order.

Antiphase Boundary Energy Determination in Superlattices based on the BCC Lattice using the Cluster Variation Method. C.G.Schon, R.Kikuchi: Zeitschrift für Metallkunde, 1998, 89[12], 868-78