Flame Spray Synthesis of Yttrium Oxide Powders for Transparent Ceramics
摘要
The influence of the carbamide concentration and the yttrium nitrate–to–carbamide ratio on the morphology and particle size distribution of yttria powders synthesized by flame spray pyrolysis was investigated. Particles with a median size ranging from 400 to 1300 nm were obtained. Thermodynamic modeling of the precursor combustion reaction was carried out, and the staged decomposition of aqueous solutions of yttrium nitrate with carbamide and glycine was studied by differential scanning calorimetry (DSC). It was established that the type of fuel affects particle morphology due to differences in the precursor decomposition mechanisms. Vacuum sintering of the synthesized powders made it possible to obtain Y2O3 ceramics with a grain size of 8.2–9 µm.