Cermet hard material coating composite and process for its production

: Endler, I.; Wolf, E.; Leonhardt, A.; Richter, V.

Abstract
The invention relates to a cermet hard material coating composite with excellent wear characteristics. During its production, no brittle intermetallic phases should occur and a diminution in strength is to be avoided. Thus a hard material coating is applied to a cermet substrate which is nitrided or carbonitrided to a depth of 10 m. The coating consists of one or several hard material coatings formed from a nitrogen-containing hard material compound or a nitrogen-containing hard material mixture consisting of one or several elements of the IV to VI subgroups of the periodic system and/or borium and/or aluminium and/or silicon and/or carbon. In production, a cermet substrate is first subjected to a nitriding or carbonitriding treatment at a temperature of up to 700 degrees C for a period of 5 to 120 minutes. This is followed by a low-temperature coating process to deposit one or several hard material coatings. Temperatures of up to 700 degrees C are applied. The invention is prefera bly used with cermet materials which mainly consist of titanium carbonitride as the hardness material and a nickel/cobalt binder. The compounds according to the invention are particularly suitable for use as cutting tools in metal cutting operations.