| 摘要 |
Provided is a coating layer for cutting tools, as a hard coating layer stacked and formed in the sequence of a TiN layer, a TiCN layer, a bonding layer, an alumina (Al2O3) layer, and a cover layer from the bottom by using a chemical vapor deposition (CVD) method on a parent material, able to improve cutting performance, because surface residual stress of the coating layer may be maintained in a compressive stress state by adjusting a composition of the cover layer without using a separate additional process, such as a blasting operation, or a mixed process of CVD and physical vapor deposition (PVD), and simultaneously the cover layer may also be used as a wear-resistant layer. The coating layer according to present invention is formed on a surface of a parent material by using a CVD method, in which the coating layer includes an alumina layer formed of an alpha-phase, disposed on the parent material and composed of a composite structure having a columnar crystal structure and an equiaxed crystal structure mixed therein, and a cover layer formed of AlxTiySizCrwN (herein, x+y+z+w=1, x>=0.75, y>=0.2, 0@z@0.06, 0@w@0.08) and disposed on the alumina layer.
|
