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:
Oct. 28, 1997
Filed:
Sep. 07, 1994
Hironori Yoshimura, Ibaraki-ken, JP;
Tetsuya Tanaka, Ibaraki-ken, JP;
Yoshikazu Okada, Ibaraki-ken, JP;
Mitsubishi Materials Corporation, Tokyo, JP;
Abstract
The present invention concerns a tungsten carbide base cutting tools formed on sintered hard alloy substrate material. Multiple hard coatings are deposited on the Co-enriched surface layer of the substrate material, and Co-enriched surface layer occurs within a surface layer region that is 50 .mu.m from an interface of said substrate material, wherein the Co content in said surface layer that is 5-10 .mu.m from an interface of said substrate material is within a range from 15-25% by weight; wherein the Co content in said surface layer is more than the Co content in the core, and wherein the content of the carbides of Ti, Ta and Nb is lower than that in the core. The multilayer coating consists of a primary coating of TiCN, a secondary coating of Al.sub.2 O.sub.3 and the surface coating consisting of at least one of TiCN and TiN. The interface between the substrate material and the primary coating is provided with a first intermediate coating consisting of TiN. The interface between the primary coating and the secondary coating is provided with a second intermediate coating consisting of at least one layer of TiC, TiCO or TiCNO.