Surface coating refers to the formation of a coating or coating on the surface of the substrate by physical or chemical methods, which is characterized by the fact that the substrate does not participate in the formation of the coating. Common processes include thermal spraying, plasma spraying, vacuum plating, electroplating, electroless plating, vapor deposition and magnetron sputtering.
The copper coating with good combination with the matrix was prepared on the surface of titanium Ti-6Al-4V (Grade 5) by electroplating copper sulfate. Under the same friction and wear conditions, the wear rate of the copper coating is much lower than that of the titanium Ti-6Al-4V (Grade 5) matrix, mainly because the copper wear chips shed during the friction process play a role in lubricating and protecting the matrix during the subsequent friction process improved the surface hardness and wear resistance of titanium alloy by plating iron on the surface of titanium alloy, and the improvement effect of iron plating on the friction and wear properties of titanium alloy is better than that of nickel plating and hard chromium plating. A Ni-P alloy layer was prepared on the surface of titanium Ti-6Al-4V (Grade 5) by electroless plating, which improved the surface hardness and wear resistance of titanium Ti-6Al-4V (Grade 5). After the coating was kept at 600 ℃ for 1 h, the wear rate of the coating under the same wear condition was minimal, and it had better wear resistance.
The friction and wear behavior of titanium alloy is affected by many factors. Due to the complexity of the friction and wear problem, the study should pay attention to the synergistic effect among various influencing factors, and also consider the connection and difference of the wear behavior of titanium alloy under different conditions.
The existing surface treatment technology can improve the wear resistance of titanium alloy to a certain extent, but most of these surface treatment technologies have high cost, large energy consumption, complex process and easy to cause environmental pollution and other problems, more importantly, the surface hardening layer prepared by these technologies is shallow, generally only tens to hundreds of microns. When the wear occurs under a large load and a long time, the actual use effect is not good. In order to make the titanium alloy applied to the conditions of large loads, the improvement of the wear resistance of the titanium alloy should be carried out from the following aspects: (1) The existing surface treatment process should be optimized to explore the process plan that can effectively increase the depth of the surface hardening layer of the material; (2) Through the preparation of composite materials, alloy composition optimization and other methods to introduce reinforcement phase in titanium alloy materials, so that its friction and wear properties are improved from the surface to the inside.
