Tool coating structure
Coating structure is generally divided into single coating, multi coating, composite coating, gradient coating and nano structure coating.
Single coating, also known as common coating, is composed of only one component, which is stable in the longitudinal growth direction of the film. In the early development of PVD technology, single coating technology has been used, typical single coating is TiCN and so on.
Multi coating is composed of films with stable composition and different properties. The common multilayer coating consists of two kinds of different films, and the number of layers can be more than ten. The minimum size of each film is tens of nanometers, such as A1N + tin coating. Compared with single-layer coating, multi-layer coating can effectively inhibit the growth of coarse grain structure and improve the coating structure.
The CBN tool with PCD multilayer coating structure can be applied to a wide range of machining fields of continuous and intermittent cutting, and its wear resistance and damage resistance are greatly improved
Ticn-al2o3-tin multilayer coating is applied to the blade. The TiCN in the inner layer of the coating has strong binding force and strength with the substrate. As an effective heat barrier, the Al2O3 in the middle can allow higher cutting speed. The TiCN in the outer layer ensures the wear resistance of the front and back cutting surfaces. The tin in the outer layer of golden yellow makes it easy to identify the wear state of the blade
Tin and A1N can form a kind of nano multilayer coating, the number of layers can reach more than one thousand, its bonding strength with the matrix is high, the hardness of the coating is close to CBN, the oxidation resistance is good, the peel resistance is strong, and it can significantly improve the surface roughness of the tool, its life is 2-3 times of tin and TiAlN coating