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:
Mar. 31, 2009
Filed:
Jun. 15, 2005
Takero Fukudome, Kokubu, JP;
Sazo Tsuruzono, Kokubu, JP;
Isao Yuri, Yokosuka, JP;
Tohru Hisamatsu, Yokosuka, JP;
Takero Fukudome, Kokubu, JP;
Sazo Tsuruzono, Kokubu, JP;
Isao Yuri, Yokosuka, JP;
Tohru Hisamatsu, Yokosuka, JP;
Kyocera Corporation, Kyoto, JP;
Abstract
A corrosion-resistant silicon nitride ceramics in which an adhesion enhancing layer (), a stress relaxing layer () and a crack extension preventing layer () are laminated in this order on a ceramic substrate () composed mainly of silicon nitride, and a surface corrosion-resistant layer () composed mainly of zirconium oxide stabilized by an element of the groupof the periodic table is laminated. The thermal expansion coefficient (α) of the ceramic substrate (), the thermal expansion coefficient(α) of the adhesion enhancing layer (), and the thermal expansion coefficient (α) of the stress relaxing layer (), the thermal expansion coefficient (α) of the crack extension preventing layer (), and the thermal expansion coefficient (α) of the surface corrosion-resistant layer () satisfy the following relational expressions (I) to (III):α≈α  (I)α<α  (II)α<α  (III).