Surface and Bulk States of Additives in Alumina Powder

Abstract

A significant fraction of the losses in the additive, in the crystal growth (conventional Verneuil process) of ruby, is traced to powder technology. Valence states of the additive in the powder are studied and correlated with their escaping tendencies. A working model is proposed and supported by kinetic studies on the powder. From this model is derived certain predictions which are significant to the Verneuil crystal growth of solid solutions.