The O-lattice modeling of bcc:hcp interfacial structure and the structure of massive:matrix interfaces in silver-26 at% aluminum alloy.

摘要

The structure of ledged and planar partially-coherent bcc:hcp interfaces has been modeled by extending the Bollmann O-lattice theory to permit the matching of all atom positions in the two phases. The arrays of all O-points between the bcc and hcp structures for the Burgers, Pitch-Schrader, and Potter orientation relationships have base-centered monoclinic, face-centered orthorhombic, and triclinic lattices, respectively, but all with two best-matching positions at each lattice point. Misfit-compensating ledges on Burgers-related (1100);Interphase boundary structures associated with the bcc ;The role of unrotated lines in the O-lattice modeling of interphase boundaries has been developed by means of the eigenvectors and eigenvalues of the transformation matrix. Best-matching regions defined by a given basic mismatch are shown to be ellipsoids. When the three unrotated lines are orthogonal, the principal axes of the ellipsoids lie along the unrotated lines. On a general interface defined by two unrotated lines, iso-matching contours are ellipses with their major and minor axes along the best- and worst-matching directions derived from a Lagrangian multiplier method.