Abstract: The invention concerns a cutting tool comprising a main body and a multi-layer coating applied thereto. To provide improved cutting tools which have increased resistance to comb cracking, tribochemical wear and cratering caused thereby the main body comprises a hard metal which includes 5 to 8% by weight of Co, 0 to 2% by weight of TaC, 0 to 1% by weight of NbC and 89 to 95% by weight of WC with a mean grain size of 1 to 5 ?m, and the coating has a first layer of TiAlN having a layer thickness of 1 to 5 ?m, and a second layer of aluminum oxide having a layer thickness of 1 to 4 ?m, wherein the coating further additionally includes on the second layer of aluminum oxide n alternately mutually superposedly applied layers of TiAlN and layers of aluminum oxide respectively having a layer thickness of 0.1 to 0.5 ?m, wherein n relates to each individual layer and is an even number of 0 to 10, and wherein the total layer thickness of the coating is 2 to 16 ?m and the coating is produced in the PVD process.

Abstract: The invention concerns a cutting tool comprising a main body and a multi-layer coating applied thereto. To provide improved cutting tools which have increased resistance to comb cracking, tribochemical wear and cratering caused thereby the main body comprises a hard metal which includes 5 to 8% by weight of Co, 0 to 2% by weight of TaC, 0 to 1% by weight of NbC and 89 to 95% by weight of WC with a mean grain size of 1 to 5 ?m, and the coating has a first layer of TiAlN having a layer thickness of 1 to 5 ?m, and a second layer of aluminum oxide having a layer thickness of 1 to 4 ?m, wherein the coating further additionally includes on the second layer of aluminum oxide n alternately mutually superposedly applied layers of TiAlN and layers of aluminum oxide respectively having a layer thickness of 0.1 to 0.5 ?m, wherein n relates to each individual layer and is an even number of 0 to 10, and wherein the total layer thickness of the coating is 2 to 16 ?m and the coating is produced in the PVD process.

Abstract: The invention concerns a cutting tool comprising a main body and a multi-layer coating applied thereto. To provide improved cutting tools which have increased resistance to comb cracking, tribochemical wear and cratering caused thereby the main body comprises a hard metal which includes 5 to 8% by weight of Co, 0 to 2% by weight of TaC, 0 to 1% by weight of NbC and 89 to 95% by weight of WC with a mean grain size of 1 to 5 ?m, and the coating has a first layer of TiAlN having a layer thickness of 1 to 5 ?m, and a second layer of aluminium oxide having a layer thickness of 1 to 4 ?m, wherein the coating further additionally includes on the second layer of aluminium oxide n alternately mutually superposedly applied layers of TiAlN and layers of aluminium oxide respectively having a layer thickness of 0.1 to 0.5 ?m, wherein n relates to each individual layer and is an even number of 0 to 10, and wherein the total layer thickness of the coating is 2 to 16 ?m and the coating is produced in the PVD process.

Abstract: The invention relates to a cutting insert and a method for its production, in which a hard-metal, cermet, or ceramic substrate body is coated by means of a PVD, PCVD or CVD method with a single- or multi-layer coating of carbides, nitrides, oxides, carbonitrides, oxinitrides, oxicarbides, oxicarbonitrides, borides, boron nitrides, boron carbides, boron carbonitrides, boron oxinitrides, boron oxocarbides, boron oxocarbonitrides of the elements of groups IVa to VIIa of the periodic table and/or of aluminium and/or mixed-metal phases and/or phase mixtures of the above-named compounds and, after the coating, the substrate body is subjected to dry or wet abrasion blasting using a granular blasting abrasive.

Abstract: A cutting insert is provided with a combination coating, comprising a wear-protection coating and an indicating layer. The indicating layer preferably is provided on the tool flank or flanks, meaning for radial inserts on the side surfaces and for tangential inserts on the bottom or top surface. The indicating layer is sensitive enough, so that even a short-term use of the adjacent cutting edge leaves clear traces on the indicating layer. In the process, the indicating layer is discolored and/or worn down, so that underlying layers or materials with different colors become visible. As a result of the clear color contrast or brightness contrast, used cutting edges can be identified immediately. The use of the tool flanks as indicating surfaces has proven to be particularly advantageous because a tribological and possibly unfavorable coating can be provided, without this having a negative influence on the processing result of the cutting insert.