Papers by Keyword: Topotaxy

Abstract: Misorientation can be calculated over large datasets and a theme of this paper is the usefulness of examining the results statistically. Comparing the statistics of misorientations calculated from neighbouring pixels (or grains) with those calculated from pairs of pixels (or grains) selected at random helps to indicate deformation and recrystallisation mechanisms. Taking boundary length into account provides a link to grain boundary energy, and boundary length versus misorientation data should be used to examine how boundaries with different misorientations evolve through time. Time lapse misorientation maps indicate how orientation changes through time at particular points in a microstructure during in situ experiments. The size of areas which have changed orientation by particular amounts can be linked to boundary length and boundary migration velocities. When dealing with different phases, the statistics of angular relationships, akin to intraphase misorientation analysis, can indicate orientation relationships in the absence of prior knowledge, which is advantageous in investigating the plethora of minerals that make up the Earth.

Abstract: This article summarizes the work of the author’s lab based on crystallography. The topics are categorized in the following three fields: The first category is crystallographic analysis of materials, the second one is correlations between crystal structure and their properties, and the third one is crystallography for processing such as epitaxy, topotaxy and templates. The examples for these categories are: (1) multilayer ceramic capacitor (MLCC); (2) microwave dielectrics of tungstenbronze-type like solid solutions, and piezoelectric materials langasite (La3Ga5SiO14); (3) thin film growth of GaN or AlN on sapphire for example of epitaxy, hydroxy-apatite grown on diopside for topotaxy, and template growth of microwave dielectrics for template. Crystallography is useful in all studies, but is not almighty. Interdisciplinary study between crystallography and solid state physics is necessary to make clear the mechanism of the properties.