Twin Junctions in Monoclinic Zirconia

Analysis of high-resolution transmission electron microscopy images of the microstructure of monoclinic zirconia film has revealed that some areas are built entirely of twins. Twin boundaries form triple and quadruple junctions. While the misorientations of the constituent boundaries are completely balanced at quadruple junctions, there is a small rotational mismatch at the junctions of three twin boundaries. This mismatch is compensated by wedge disclinations. Crystallography of the triple junctions is considered and factors stabilizing intrinsic junction disclinations are discussed.