Process for producing zirconium oxide sintered body
AssigneeHitachi Chemical Company, Ltd.
InventorsTakao Nakada, Mamoru Kamimura, Toranosuke Ashizawa
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Abstract
A zirconium oxide sintered body for an oxygen concentration sensor is produced by mixing 87.5 to 91.0% by weight of zirconium oxide powder, 8.5 to 12.3% by weight of yttrium oxide powder, 0.5% by weight or less of silicon oxide and 0.2 to 1.0% by weight of aluminum oxide, drying the resulting mixture, followed by sintering so as to make the cubic phase content in crystal phase of the resulting sintered body at ordinary temperatures 95% by weight or more. Said zirconium oxide sintered body is excellent in mechanical strength, thermal shock and ionic conductivity and can be used stably for a long period of time.
Claims6
A process for producing a zirconium oxide sintered body, which comprises wet blending 87.5 to 91.0% by weight of zirconium oxide powder to grind mixture of oxide powders, and 8.5 to 12.3% by weight of yttrium oxide powder, drying the resulting mixture, and subjecting the dried mixture to heat treatment at a temperature higher than 1,300.degree. C. and below sintering temperature, wherein the average particle size of the mixture of the oxide powders after grinding is 1 um or less;
- mixing the heat-treated mixture with 0.5% by weight or less of silicon oxide and 0.2 to 1.0% by weight of aluminum oxide, and then sintering the mixture to obtain 95% by weight or more of a cubic phase in a crystal phase at ordinary temperatures.
Dependencies are inferred from the claim text.