Formation and Orientation of Low Energy MgO/Pd, Al2O3/Pd and TiO2/Pd Interfaces

Abstract

SummaryThe results of this study indicate that oriented α-Al2O3 and TiO2 particles with planar facets suitable for HREM studies can be produced in Pd by internal oxidation. A single high symmetry cube-on-cube orientation relationship has been observed for cubic MgO oxide particles in Pd. Six orientation relationships have been observed for trigonal α-Al2O3 oxide particles in Pd. Parallelism of the low misfit [1100]M// [110]O common direction appears to be the dominant factor for the preferred orientations with facets corresponding to parallelism of low index planes of Pd and α-Al2O3. For the tetragonal TiO2 phase in Pd, eight orientation relationships have been observed with orientations controlled primarily by oxide nucleation on {111} plane of Pd. For this system, the particle shape is controlled by anisotropy in growth kinetics.