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. 03, 1997
Filed:
Oct. 24, 1994
Isao Ikeda, Yokohama, JP;
Michiyasu Komatsu, Yokohama, JP;
Kabushiki Kaisha Toshiba, Kanagawa-ken, JP;
Abstract
A silicon nitride-based sinter contains as component elements thereof magnesium in the range of from 0.1 to 1.5% by weight, aluminum in the range of from 0.1 to 3.5% by weight, carbon in the range of from 0.01 to 6% by weight, and oxygen in the range of from 0.2 to 5% by weight, the balance consisting essentially of silicon, nitrogen, and impurities. This sinter is obtained by sintering a ceramic mixture comprising 0.5 to 6% by weight of a MgO.Al.sub.2 O.sub.3 spinel structure, 0.1 to 20% by weight of silicon carbide, not more than 1% by weight of silicon oxide, and the balance substantially of silicon nitride and impurities. Owing to the incorporation of the MgO.Al.sub.2 O.sub.3 spinel structure and silicon carbide, the produced silicon nitride-based ceramic acquires an outstanding ability to resist corrosion caused by such chemicals as acids and alkalis (resistance to chemicals) without impairing such inherent characteristic properties of silicon nitride as strength, resistance to abrasion, and resistance to heat.