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:
Jan. 18, 2005
Filed:
May. 04, 2004
Tomoko Suzuki, Kawasaki, JP;
Atsushi Omote, Sagamihara, JP;
Jun Kuwata, Tokyo, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
Using as a negative thermal expansion material a double oxide containing at least partly a compound represented by the chemical formula: RQ,O, (wherein R is Zr, Hf or a tetravalent metallic element represented by a mixture system of these, and Q is a hexavalent metallic element selected from W and Mo), and using as a positive thermal expansion material a material containing at least partly a compound represented by the chemical formula: MQX, (wherein M is Mg, Ca, Sr, Ba, Ra or a divalent metallic element represented by a mixture system of any of these, Q is a hexavalent metallic element selected from W and Mo, and X is an element selected from O and S), these are mixed preferably in a weight ratio of 1:1 and are synthesized to obtain a material whose coefficient of thermal expansion is substantially zero over a wide temperature range, i.e., a zero thermal expansion material. Using this zero thermal expansion material, high-precision and high-performance practical component parts can be obtained.