Orientation relationships between complex low symmetry oxides: Geometric criteria and interface structure for yttrium aluminate eutectics

摘要: Abstract Solidified eutectics of yttrium–aluminum perovskite (YAP)–yttrium–aluminum monoclinic (YAM) and YAM–yttria were observed by transmission electron microscopy optical microscopy. Orientation relationships (ORs), interphase boundary orientations some structures determined compared to those predicted various geometric criteria. Six ORs found in YAP–YAM two YAM–yttria. Near-coincidence site lattices (NCSLs) calculated for each eutectic. OR predictions based on NCSL energy minimization NCSLs the ORs. Predictions symmetry overlap criteria edge-to-edge model also observations. All common had coincident low-index real-space lattice vectors that consistent with model. Three these matching planes cozonal directions Issues application boundaries between complex, low materials are discussed.