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:
Sep. 06, 2005
Filed:
Sep. 07, 2001
Hideki Kato, Aichi, JP;
Yuki Hatano, Aichi, JP;
Hideaki Yukimachi, Gifu, JP;
NGK Spark Plug Co., Ltd., Aichi, JP;
Abstract
A ceramic cutting tool including a ceramic base memberof a tool main bodywhich is formed of a composite ceramic which contains a hard phase dispersed within an alumina matrix phase. The hard phase contains, as a predominant component, one or more elements selected from hard-phase-forming metal elements M in the form of at least one of a carbide, nitride, or boride, or in the form of a solid solution of at least two selected from the carbide, nitride and boride. The hard-phase-forming metal elements M include Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W and Si. The surface of the ceramic base memberis covered with a coating layer, which contains titanium carbonitride or titanium nitride as a predominant component. The coating layerhas an average crystal-grain size of 0.1 to 0.5 μm as observed on the surface, and an average thickness of 0.5 to 2 μm. The coating layeris formed by a CVD at a low to medium temperature range of 750 to 900° C. The ceramic cutting tool can be fabricated at low cost and can secure stable cutting performance over a long period even when the tool is used under severe cutting conditions under which large thermal and mechanical loads act on the tool.