| 摘要 |
The invention relates to materials for coating metal pieces subjected to friction, such as friction couplings, to criteria for selecting materials and optimizing mechanical and tribological characteristics of the coating layers and to processes for carrying out nanostructured and microstructured coatings with repetitive structure and modulated composition. The claimed coatings have a quasi-unique layer structure or a repetitive structure in identical packets, each packet being made of 2...5 materials, such that the coating layers gain maximal values for 6 physical and chemical properties: good adherence to substrate and high cohesion between layers, high hardness (H), increased resistance to elastic and elastoplastic deformation (E and H/E), low friction coefficient ( μ < 0.1), high thermal conductivity ( λ ), and resistance to corrosion and thermal oxidation. The claimed materials can be simple materials, such as chemical elements or composite materials, such as organic or inorganic compounds, and the selection thereof is made so as to individually ensure maximal values for the 6 physical and chemical properties presented above. The optimization of the mechanical characteristics, as claimed by the invention, is carried out by selecting a number of 2...5 component materials of the coating layers whose characteristics are selected depending on the working conditions of the friction coupling and on the coating cost, the number of stages taken into account upon carrying out the tribological coatings being an odd number 3-5-7 equal to the number of materials used or higher, depending on the experimentally-obtained results. The claimed processes can be of the vacuum vapour deposition type, such as magnetron type cathode sputtering in DC, pulsed DC or RF, or nano/micro-powder deposition in open atmosphere such as cold/thermal/electrostatic spray with cold and complex plasma. |
