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:
Jul. 02, 2019
Filed:
Oct. 30, 2017
Ngk Insulators, Ltd., Nagoya, JP;
Kiyoshi Matsushima, Nagoya, JP;
Morimichi Watanabe, Nagoya, JP;
Kei Sato, Tokai, JP;
Tsutomu Nanataki, Toyoake, JP;
NGK Insulators, Ltd., Nagoya, JP;
Abstract
An alumina sintered body according to the present invention includes a surface having a degree of c-plane orientation of 5% or more, the degree of c-plane orientation being determined by a Lotgering method using an X-ray diffraction profile obtained through X-ray irradiation at 2θ=20° to 70°. The alumina sintered body contains Mg and F, a Mg/F mass ratio is 0.05 to 3500, and a Mg content is 30 to 3500 ppm by mass. The alumina sintered body has a crystal grain size of 15 to 200 μm. When a field of view of 370.0 μm long×372.0 μm wide is photographed with a 1000-fold magnification and the photograph is visually observed, a number of pores having a diameter of 0.2 to 0.6 μm is 250 or less.