Ceramics-Silikáty 49 (4) 252-258 (2005)

PREPARATION OF LEUCITE POWDERS WITH CONTROLLED PARTICLE SIZE DISTRIBUTION

M. Novotná, A. Kloužková, J. Maixner, V. Šatava

Leucite ceramics having high fracture toughness and suitable thermal expansion being useful for making ceramic-fused-tometal restorations represents a very promising material for dental applications. The aim of our work is to replace existing technologies based on the crystallization from a melt by preparation of a composite material in which leucite and glassy matrix are synthesised separately. Both these phases are subsequently homogenised and sintered in a dentist laboratory. This technology ensures reproducible control of leucite ceramics microstructure, which is requited to improve its fracture toughness and persistence. In the present study preparation of leucite powders with controlled particle size distribution was investigated. Leucite was prepared by ion exchange of analcime, the degree of ion exchange was determined by XRD and XRF analysis. As the properties of analcime employed for the reaction are critical for resulting leucite, the effect of process parameters and starting compositions on the particle size, shape and structure was studied.

Keywords: Leucite, Preparation, Particle size distribution