Affiliation:
1. Shenyang Institute of Engineering
Abstract
Single crystal of Rutile has been grown successfully by the flame fusion method by using high purity (4N5) ultrafine titania powder as starting material. The effects of growth atmosphere, growth rate and temperature gradient in the chamber on crystal growing were investigated and the specific growth conditions have been defined. The annealing of the as-grown crystals was performed in the oxygen and in the air respectively. It was shown that growth atmosphere where the oxygen partial pressure is higher than that of the oxygen decomposing pressure at the liquid-solid interface is a necessary condition for growing perfect crystals. In addition to reducing thermal stresses, the more important role of annealing is to eliminate oxygen vacancies by oxidization reaction. The annealing time can be considerably shortened in an oxygen atmosphere as compared to in the air and the grown crystal has more perfect structure.
Publisher
Trans Tech Publications, Ltd.