Forming processes, microstructure and thermal stability of fibrous zirconium dioxide stabilized by magnesium and yttrium oxides are investigated. It is shown that the stabilization of tetragonal or cubic structures can occur at low temperatures during forming of oxide fibers. Due to the high dispersion of the oxide particles and the fibers reactivity, cubic solid solutions in binary systems ZrO2-MgO, ZrO2-Y2O3 are obtained with stabilizing additives contents equal to 13.3 and 12 mol%, respectively. Binary and ternary solid solutions keep their thermal stability up to 2000°C in air. In nitrogen a partial nitrogenation of ZrO2 occurs and by interaction with amorphous carbon zirconium carbides are formed. In this case the ternary solid solution decomposes into three solutions of cubic structure and close crystal lattices parameters.
KeywordsSolid Solution Volume Diffusion Yttrium Oxide Ternary Solid Solution Zirconium Carbide
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