The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 12, 1981
Filed:
Oct. 01, 1979
Tadahiko Miyoshi, Hitachi, JP;
Takeo Yamazaki, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Oxygen sensor ceramic of solid electrolyte of zirconia-yttria system comprises aggregates of cubic zirconia grains having an average grain size of 2-10 .mu.m and monoclinic zirconia grains having an average grain size of 0.2-1 .mu.m, the appregates of the cubic zirconia grains being in contact with one another, and the monoclinic zirconia grains being distributed as aggregates in clearances among the aggregates of the cubic zirconia grains, and has a high thermal shock resistance, a high mechanical strength and a resistivity equal to that of the ceramic consisting only of cubic zirconia grains. The oxygen sensor ceramic is prepared by mixing zirconia powder having a grain size of 0.1-0.5 .mu.m with 4-8% by mole of yttria powder having an average grain size of 0.5-5 .mu.m, on the basis of total mixture, and molding and firing the mixture at 1,400.degree.-1,550.degree. C.