Sintering of Transparent Yttria Ceramics in Oxygen Atmosphere

A novel method is reported for the preparation of transparent polycrystalline yttria ceramics in oxygen atmosphere. Zirconia and other additives were added to control the grain growth. Pores can be eliminated clearly at a temperature < 1650 degrees C with the grain size around 1 mu m. The grain growth kinetics and the mechanisms controlling grain growth were studied. Sintering in oxygen atmosphere is beneficial for making samples with a big size at low cost and avoiding the posttreatment of samples sintered in vacuum or hydrogen atmosphere.