| 摘要 |
<p>The present invention relates to cutting insert for milling of extremely highly alloyed grey cast iron comprising a substrate and a coating and method of making. The cemented carbide substrate consists of WC, 3-8 weight-% Co and <0.5 weight-% carbides of metals from groups IVb, Vb or VIb of the periodic table. The coating comprises a first, innermost layer of TiC x N y O z with x+y+z=1, y>x and z<0.2, preferably y>0.8, and z=0, with equiaxed grains with size <0.5 µm and a total thickness of 0.1-1.5 µm, a layer of TiC x N y with x+y=1, x>0.3 and y>0.3, preferably x‰¥0.5, with a thickness of >3-5 µm with columnar grains with an average diameter of <5 µm, a layer of a smooth, fine-grained, grain size 0.5-2 µm, º-Al 2 O 3 with a thickness of 0.5-3 µm and an outermost layer of TiN with a thickness of <2 µm.</p> |
