摘要 |
The present invention relates to a cutting tool comprising a body (1) of a sintered cemented carbide or cermet, ceramic or high speed steel on which, at least on the functioning parts of the surface of the body, a thin, adherent, hard and wear resistant coating (2) is applied. The coating comprises a laminar structure of refractory compounds in a polycrystalline, repetitive form: (MLX/Al2O3) lambda (MLX/Al2O3) lambda / (MLX/Al2O3) lambda / (MLX/Al2O3) lambda /... where the alternating sublayers consist of metal nitrides (or carbides) and crystalline alumina (4) of the alpha( alpha )- and/or the gamma( gamma ) phase, preferably of metal nitrides and crystalline alumina of the gamma phase. The metal elements in the layers MLX (3) are selected from Ti, Nb, Hf, V, Ta, Mo, Zr, Cr, W and Al. The repeat period lambda (5) is essentially constant through the entire multilayered structure, and larger than 3 nm but smaller than 100 nm. The total thickness of said multilayered coating is larger than 0.5 mu m but smaller than 20 mu m. |