摘要 |
The present invention discloses coated cutting tool inserts particularly useful for turning of nodular cast iron preferably at high speeds, comprising a cemented carbide substrate 5-9 wt-% Co and 1-5 wt% cubic carbides and balance WC of 86-94 wt-%, and a coating comprising a first layer of TiC x N y O z with equiaxed grains, a layer of TiC x N y O z with a thickness of >10-15 µm with columnar grains, a layer of TiC x N y O z with a thickness of 0.1-2 €µm and with equiaxed or plate-like grains, a layer of ±-Al 2 O 3 with thickness 3-8 µm, an outer layer of a multilayered structure of TiN+TiC with TiC being the outermost layer and a total thickness of 0.5-2 µm and the outer coating layer has been removed in the edge line and on the rake face so that the ±-Al 2 O 3 layer is on top along the cutting edge line and on the rake face and the outer TiC layer is the top layer on the flank face. |