Ceramics zirconia

Zirconia ceramics represent a fairly new class of advanced stmctural materials (see Zirconium and zirconium compounds). Their potential use in stmctural appHcations was first realized in the mid-1970s. Since then numerous pubHcations have appeared devoted entirely to these materials (76—81). 

R. Stevens, Zirconia and Zirconia Ceramics, 2nd ed.. Magnesium Elektron PubHcation No. 113,1986. 

Application of AES to zirconia ceramics has been reported by Moser et al. [2.146]. Elemental maps of Al and Si demonstrate the grain boundary segregation of small impurities of silica and alumina in these ceramics. 

The basic zirconia oxygen sensor design is illustrated in Fig. 13.52, which shows the principle of the zirconia solid oxygen-ion electrolyte. The sensor consists of a closed-end tube of ceramic zirconia ZrO )). The zirconia ceramic... 

The co-precipitation technique starts with an aqueous solution of nitrates, carbonates, chlorides, oxychlorides, etc., which is added to a pH-controlled solution of NH4OH, allowing the hydroxides to precipitate immediately. This method requires water-soluble precursors and insoluble hydroxides as a final product. The hydroxides are filtered and rinsed with water when chlorides are employed as starting materials and chlorine is not desired in the final product. After drying the filtrate, it is calcined and sintered. This method is being applied very successfully for oxygen-ion conducting zirconia ceramics [30],... 

Figure 6.16 Car exhaust sensor (schematic) fitted with a stabilized zirconia ceramic tube as electrolyte.

Zirconia, calcium oxide stabilized, 5 622 strength, 5 617t Zirconia ceramics... 

SYNTHESIS AND CHARACTERIZATION OF POLY (MAGNESIUM ACRYLATE) AND POLY(ZIRCONYL ACRYLATE) TOWARDS THE FORMATION OF MAGNESIUM PARTIALLY STABILIZED ZIRCONIA CERAMICS... 

The effect of highly localized loading on the surface of yttria-stabilized zirconia ceramic was investigated by polarized Raman microprobe spectroscopy. Figure 17.2a-d shows a micrograph of an indentation print, a map of... 

Jimenez-Melendo, M., and Dominguez-Rodriguez, A., Like-metal superplasticity of fine-grained Y203-stabilized zirconia ceramics , Phil. Mag, 1999, A 79, 1591— 608. 

For refractory applications, when the mixed oxide route is followed, temperatures as high as 1900 °C are necessary to sinter to high density. The high interest in SOFCs has stimulated efforts to develop novel fabrication routes to zirconia ceramics and yttria-stabilized sub-micron sized powders have been prepared which sinter to 95% theoretical density at a temperature as low as 1150 °C [4],... 

Stabilized zirconia — Figure. Oxygen ionic conductivity of stabilized zirconia ceramics as a function of reciprocal temperature at different dopant concentrations. See [ii] for details... 

R. H. Dauskardt, D. B. Marshall, and R. O. Ritchie, Cyclic Fatigue Crack Propagation in Magnesia-Partially-Stabilized Zirconia Ceramics, J. Am. Ceram. Soc., 73[4], 893-903 (1990). 

Fabrication Technology. Stabilizing additives must be uniformly distributed within the starting powders for zirconia ceramics. 

Yttria and the rare earths find a variety of specialized applications. Y2O3 is used to produce yttria stabilized zirconia ceramics. Cerium, neodynium, and didymium oxides (a... 

Zhou, X.D., Scarfino, B., and Anderson, H.U., Electrical conductivity and stability of Gd-doped ceria/Y-doped zirconia ceramics and thin films. Solid State Ionics, 2004, 175 19-22. 

Jiang, S.S., Schulze, W.A., Amarakoon, V.R.W., and Stangle, G.C., Electrical properties of ultrafine-grained yttria-stabilized zirconia ceramics, Journal of Materials Research, 1997, 12, 2374-2380. 

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