Zirconia sintering aids

Other potential applications are ceramic powders coated with their sintering aids, zirconia coated withyttria stabilizer, tungsten carbide coated with cobalt, or nickel, alumina abrasive powders coated with a relatively brittle second phase such as MgAl204 and plasma spray powders without the segregation of alloying elements. 

Zirconia is the third common sintering aid encountered. It is used at the 5% by weight level to give high density products and grain-boundary crystals of Si2N20 and Zr02. 

The technological benefits of the CAPAD method such as the low sintering temperature, the short sintering time with an increased heating rate, as well as the removal of sintering aids, make it an attractive consolidation technique for zirconia ceramics."" ... 

The values of the creep parameters (p, n and Q) identifying the superplastic behaviour of ceramic-related materials are not unique to such materials, nor to the same type of materials. As shown in the review papers, these parameters are very similar in tension as in compression in zirconia-based materials (probably the most widely studied ceramics in the widest experimental conditions), although that depends strongly on the purity of the ceramics 5,7 however, their behaviour seems to be very different in compression than in tension when an aid-sintering phase is necessary during the processing, as in silicon carbide and silicon nitride ceramics.8... 

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