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:
Jun. 16, 1992
Filed:
Feb. 04, 1991
Nobuhiro Hayakawa, Aichi, JP;
Hiroyuki Ishiguro, Aichi, JP;
Takeshi Kitano, Aichi, JP;
Yutaka Adachi, Aichi, JP;
NGK Spark Plug Co., Ltd., Nagoya, JP;
Abstract
As a solid electrolyte suitable for use in oxygen sensors a partially stabilized zirconia, which essentially consists of 4.5-6.0 mol % of Y.sub.2 O.sub.3 and the balance of ZrO.sub.2 and is constituted of tetragonal and cubic crystals, is produced by using a coprecipitated powder of a solid solution of ZrO.sub.2 and Y.sub.2 O.sub.3 as the raw material and performing sintering of a green body at a temperature not higher than 1500.degree. C. The ZrO.sub.2 -Y.sub.2 O.sub.3 powder has a mean particle size not larger than 1 .mu.m and a specific surface area in the range from 2.5 to 7 m.sup.2 /g and is required to be not more than 0.2 wt % in the content of unwanted SiO.sub.2 so that the sintered solid electrolyte may be as low as possible in the content of SiO.sub.2. The obtained solid electrolyte has good mechanical properties and exhibits sufficiently high withstand voltage.