Sandvik Intellectual Property Ab

Helen Blomqvist

Mats Ahlgren

Maria Åstrand

Johan Böhlmark

A coated cutting tool includes a substrate and a PVD coating having an outermost zone C being a nitride, carbide, boride, or mixtures thereof, of Si and at least two additional elements selected from Al, Y, and groups 4, 5 or 6 of the periodic table and zone C is free from a compositional gradient of an average content of Si. Zone C has a laminar, aperiodic, multilayered structure with alternating individual layers X and Y having different compositions from each other. The coating further includes a zone A closest to the substrate, a transitional zone B, where zone A is essentially free from Si, zone B includes a compositional gradient of the average content of Si, and where the average content of Si is increasing towards zone C.

Multilayered coated cutting tool

The present invention relates to a coated cutting tool insert of cemented carbide with coating including at least one layer of TiAlN deposited by PVD-technique. The layer has x=0.4-0.6 with a compressive residual stress of &#x3e;4-6 GPa and a thickness of 1.5-5, preferably 2.5-4 &#x3bc;m. Both the I(111) and I(200) are &#x3c;7.5, preferably &#x3c;5, times, the intensity average noise level. Good adhesion despite high compressive stress is obtained if the layer is deposited by cathodic arc evaporation technique at a bias in the range &#x2212;90&#x3c;U&#x3c;&#x2212;50V, preferably &#x2212;80V&#x3c;U&#x3c;&#x2212;60V.

Growing community of inventors

Enskede Gård, Sweden

Helen Blomqvist