Insert
AssigneeSandvik Intellectual Property AB
InventorsLeif Åkesson, Toril Myrtveit, Ibrahim Sadik
Life of this patent
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Abstract
The present invention relates to a coated cemented carbide milling insert for either wet or dry machining of cast iron such as nodular cast iron (NCI), grey cast iron (GCI), austempered ductile iron (ADI) and compacted graphite iron (CGI) where a high wear resistance and an excellent resistance against thermo cracks are required comprising: a substrate comprising from about 5 to about 7 wt-% Co, from about 140 to about 250 ppm Ti+Ta and balance WC with a weight ratio Ti/Ta of from about 0.8 to about 1.3 and a PVD-layer consisting of AlxTi1−xN, with x=from about 0.50 to about 0.70 and with a thickness of from about 1 to about 10 μm. The invention also relates to a method for making cutting tool inserts and their use.
Claims15
Cutting tool insert comprising a cemented carbide substrate and a coating wherein:
- the substrate comprises from about 5 to about 7 wt-% Co, from about 140 to about 250 ppm Ti+Ta and balance WC with a weight ratio Ti/Ta of from about 0.8 to about 1.3, a coercivity, Hc, of from about 15.5 to about 19.5 kA/m, and a CW-ratio of from about 0.81 to about 0.95, and
- the coating comprises a homogeneous layer of AlxTi1−xN, with x =from about 0.5 to about 0.7 with a total thickness of from about 0.5 μm to about 15 μm, on the rake side and from about 2 μm to about 7 μm on the flank side.
Method of making a cutting tool insert comprising a cemented carbide substrate and a coating comprising providing a substrate comprising from about 5 to about 7 wt-% Co, from about 140 to about 250 ppm Ti+Ta and balance WC with a weight ratio Ti/Ta of from about 0.8 to about 1.3, with a coercivity, Hc, of from about 15.5 to about 19.5kA/m, and a CW-ratio of from about 0.81 to about 0.95 and depositing onto said substrate a coating comprising a homogeneous layer of, AlxTi1−xN, with x =from about 0.5 to about 0.7, the total thickness of the coating of from about 0.5 μm to about 15 μm on the rake side and from about 2 to about 7 μm on the flank side using cathodic arc evaporation using two or three pairs of arc sources consisting of pure Ti and/or TiAl alloy(s), in an N2 or mixed N2+Ar gas atmosphere.
Dependencies are inferred from the claim text.