| 摘要 |
PURPOSE: A coating comprising a layer containing boron and nitrogen is required for providing satisfactory adhesion to a substrate (2) and applying to cutting inserts comprised of cermets or ceramics using CVD (chemical vaporization deposition) techniques. CONSTITUTION: The coating (12) comprises a base layer (4) on a substrate (2); a first intermediate layer (6) on the base layer (4); a second intermediate layer (8) on the first intermediate layer (6); and a layer containing boron and nitrogen (10) on the second intermediate layer (8). The base layer (4) comprises one or more elements selected from titanium, hafnium and zirconium, The first intermediate layer (6) is a layer containing boron and carbon. The second intermediate layer (8) is a layer containing boron, carbon and nitrogen, wherein the ratio boron:nitrogen is between 29:71 to 54:46 and the content of carbon is 11-26 atom%. The layer (10) contains boron of 38-85 atom%, and preferably comprises boron nitride, more preferably cubic boron nitride. |
