Zirconia has been recently introduced in prosthetic dentistry for the fabrication of crowns and fixed partial dentures, in combination with CAD/CAM techniques. Zirconia stabilized with Y2O3 has the best properties for these applications. This project aims at producing cast Zirconia blocks primarily for dental application that is more cost effective and biocompatible in comparison to the commerc...

First measurements of oxygen grain boundary diffusion coefficients in nanocrystalline yttria-doped ZrO(2) (n-ZrO(2).6.9 mol % Y(2)O(3)) are presented. The (18)O diffusion profiles measured by secondary ion mass spectroscopy are much deeper in the nanocrystalline specimens than in single crystals. An oxygen diffusivity, D(B), in the grain boundaries can be deduced, which is approximately 3 order...

Polymer-derived amorphous SiCN has excellent high-temperature stability and properties. To reduce the shrinkage during pyrolysis to improve oxidation resistance, Y2O3 was added as a filler. In this study, polymer-derived SiCN–Y2O3 composites were fabricated by mixing polymeric precursor of with submicron powders in different ratios. The mixtures cross-linked pyrolyzed argon. processed using fie...

The post-processing treatment response of a Y2O3 oxide-dispersion-strengthened (ODS) and γ/γ′-strengthened Ni–8Cr–5.5Al–1Ti (wt.%) model alloy, produced by laser powder bed fusion (L-PBF) is studied. solutionizing at 1260 °C induces significant recrystallization the initial elongated grain microstructure, characteristic L-PBF processing. Grain-boundary pinning dispersoids affects efficiency, le...

The hot deformation behavior and rolling based on the processing map of a nano-Y2O3 addition near-? titanium alloy were investigated. isothermal compression tests conducted at various temperatures (950?–1070 °C) strain rates (0.001–1 s?1), up to true 1.2. flow stress was strongly dependent temperature rate, decreasing with increased decreased rate. average activation energy 657.8 kJ/mol 405.9 i...

Bistability is common in nonlinear dynamical systems, but there have been no reports of intrinsic instabilities in black-body emission of optically excited media. Intrinsically bistable photo-luminescence has been reported however in Yb-doped heavy metal halide crystals at cryogenic temperatures and also in room temperature experiments in rare-earth-doped laser glass and transition metal laser ...

Powders of Y2O3 co-doped with Yb3+ and Er3+ composed of well-crystallized nanoparticles (30 to 50 nm in diameter) with no adsorbed ligand species on their surface are prepared by polymer complex solution method. These powders exhibit up-conversion emission upon 978-nm excitation with a color that can be tuned from green to red by changing the Yb3+/Er3+ concentration ratio. The mechanism underly...