Composites of yttria-stabilized zirconia (YSZ) with Sr-doped LaCrO3 (LSC) and Sr-doped LaMnO3 (LSM) were prepared by impregnation of a porous YSZ matrix with aqueous solutions of the appropriate metal salts, followed by sintering to various temperatures. XRD measurements showed that perovskite phases formed after sintering at 1073 K, a temperature well below that at which solid-state reactions ...

In this thesis, we report on a process to obtain yttrium oxide nanosized particles doped with ytterbium and a sintering method that leads to transparent polycrystalline ceramics. First, nano-powder of yttria was fabricated from a precursor with transient morphology, i.d. yttrium hydroxynitrate platelets that decompose into spherical yttria nano-particles during calcination. The influence of dif...

Materials that can capture and store CO2 are important. Though CaO is a cheap sorbent, it is inefficient for practical purposes due to sintering and poor diffusion of CO2 through the surface-CaCO3 layer. We have developed a high performance, sintering-resistant CaO-based sorbent by uniformly nanofabricating the CaO nanocrystals on SiO2 microtubes made by organogel templated polymerization.

Two materials were prepared with composition PbMg0.3Nb0.6Zr0.1O3 (PMNZ/10) and PbMg0.32Nb0.65Zr0.03O3 (PMNZ/3). Slight modifications in lead oxide content of these materials were made to study its influence on the sintering properties. The stoichiometric PMNZ/3 gave the best results. It has a sintering temperature as low as 900°C and a relative dielectric constant of 10 000 at room temperature.

DC flash sintering of both pure and 0.5 mol.% Bi2O3-doped ZnO at a relatively high activating field of 300 V/cm has been investigated. It is demonstrated that even high-purity ZnO single crystals can “flash” at 870 C. In comparison, flash sintering occurs at a substantially lower onset temperature of 550 C in ZnO powder specimens, indicating the important roles of surfaces and/or grain boundari...

Different volume fractions (1.3, 2.6, and 7.6 Vol.%) of carbon nanotubes (CNTs) were dispersed within 8Y-TZP nanopowders. Mixed powder specimens were subsequently processed by spark plasma sintering (SPS) and effects of CNTs on the sintering process of 8Y-TZP/CNT composites was studied. Maintenance of CNTs through the SPS process was confirmed using TEM and Raman Spectroscopy. Studies on the si...

in this study, porcelain bond strength to three different alloys of gold-base, pd-ag and base-metal were compared and the effect of repeated porcelain sintering on bond strength was evaluated. the obtained results showed best bond strength of porcelain with gold-base alloy. pd-ag and base-metal alloys showed less strength respectively. during repeated sintering of porcelain, bond strength has n...

Municipal solid waste incineration fly ash is generated in a significant amount; it is classified as hazardous waste in Taiwan. In order to reduce the volume of treated fly ash, a sintering technology can be considered. However, a traditional sintering consumes too much energy because of the limit of heat transfer. Hence, a microwave process which can provide quick, uniform, and selective heati...

background: fracture load of implant-supported restorations is an important factor in clinical success. this study evaluated the effect of two techniques for screw access hole preparation on the fracture load of cement-screw retained implant-supported zirconia-based crowns. methods: thirty similar cement-screw retained implant-supported zirconia-based maxillary central incisor crowns were evalu...

Alumina-Mullite-Zirconia ceramic composites were prepared by reaction sintering of alumina, zircon mixture and the sintering aids of magnesia and titania at temperatures of 1400 and 1600 C for 2 hours. The development of different phases and microstructures of the composites were analysed to assess the relative influence of the additives on the formation of alumina-zirconia-mullite compos...