| Popis: |
In order to study and expand the application of Inconel718 alloy in high temperature environment, Co/TiN composite coating was prepared on its surface by laser cladding. Meanwhile, the tribological behavior of the coatings at room temperature (RT) and 600 ℃, and the oxidation resistance at 800 ℃ were investigated by XRD, SEM and EDS analysis, etc. The results show that the hardness of the composite coatings is 1.3-1.4 times higher than that of the substrate. The tribological properties of the coating are tested. When the TiN content is 4%(mass fraction, the same below), the anti-friction properties of the coating are the best. When 6%TiN added, the wear resistance of the coating is the best, and the wear rate can be reduced by 90.02%. In addition, the oxidation experiment shows that the Co/TiN composite coating has a certain oxidation resistance, and the oxidation rate is 8.7634 mg2·cm-4·h-1, which is not much different from the substrate.It shows that the composite coating can significantly reduce the wear rate at high temperature while retaining the oxidation resistance of the substrate, and the wear rate decreases with the increase of TiN. The wear mechanism analysis shows that the oxidation wear occurs on all coatings at 600 ℃, and the oxide film on the surface of the coatings also can reduces the wear rate at some extent. |
