Study On The Preparation Of Ceria-based Polishing Powder

The ceria-based polishing powder is a kind of most outstanding polishing material. With its unique polishing performance and quality, it is extensively applied to Hi-Tech fields, such as the optical glass, electronic product, etc. The polishing performance of ceria-based polishing powder is determined by its special physical and chemical property. And how to prepare the polishing powder of excellent performance, already become a hot subject for research.This subject has been studied since the preparation course of crystalline rare earth carbonate. Selecting proper precipitation condition, crystalline cerium carbonate can be prepared with perfect shape, suitable size and uniform distributing.Using two precipitant agents—ammonium fluorine and fluorosilicic acid to add fluorine, different rare earth fluorocarbonates are produced. By using SEM and XRD to analysis and compare the configuration, size and phase composition of two crystalline precipitations, we get the result that rare earth fluorocarbonate of simple phase composition and perfect crystal shape can be produced with the precipitant agent of ammonium fluorine.In the calcination course of rare earth carbonate, the processes of decomposition, crystallization, grain growth and cooling have been studied at first. By means of TG-DTA , SEM , XRD etc., the particles configuration, grain size, phase composition and crystallite size of calcination products, which are prepared by calcination of three materials—cerium carbonate, cerium fluorocarbonate and mixed rare earth carbonate in different calcination temperature, calcination time, cooling condition and different adding elements, have been studied too. Finally, the relationship of different calcination contion and crystallite size is also discussed.