Shape Evolution of SrTiO 3 Crystals During Coarsening in a Titania‐Rich Liquid

To identify factors that might affect capillary driving forces and interface structure‐dependent mechanisms for coarsening, we have used a stereological analysis to determine the changes in the morphology of SrTiO 3 crystals in contact with a titania‐rich liquid at 1500°C. A combination of flat and curved surfaces is observed in contact with the liquid. The (100) surface is the most common, followed by (110). A range of surfaces in the 〈100〉 zone are also found, but with a lower frequency. The areas of the {100} and {110} surfaces are approximately equal at the initial stage, but after 24 h of growth, the {100} surface area is more than twice as great as the {110} surface area. At this point, {100} surfaces make up more than 25% of the surface area in contact with the liquid. The results suggest that morphological changes during growth continuously reduce the average surface energy and interface mobility. This provides a plausible explanation for coarsening rates that decrease faster than predicted by the classical theory.