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:
Dec. 27, 1994
Filed:
Sep. 07, 1993
Yoshihiro Okawa, Kokubu, JP;
Kenichiro Miyahara, Kokubu, JP;
Kyocera Corporation, Kyoto, JP;
Abstract
A molded article is prepared from an AlN powder of a high purity without adding sintering assistant, baked in a nitrogen atmosphere without containing carbon, and is further heat-treated in a nitrogen atmosphere containing carbon in order to remove impurities in the sintered product. There is obtained a highly pure and dense sintered product which comprises mainly a phase of aluminum nitride, which has an average grain size of greater than 9 .mu.m, cationic metal impurities other aluminum, and Si, Fe and Ca in amounts smaller than predetermined values. The sintered product exhibits a very small creep rate when stress is applied thereto at high temperatures and is used as a material for high temperature uses such as a baking jig. Owing to its excellent anti-creeping property at high temperatures, tile product is suitably used as a structural material subject to stress at high temperatures for extended periods of time. When used as a baking jig, in particular, the sintered product does not adversely affect the molded articles and exhibits excellent durability.