Effect of W Powder Content on Microstructure and Friction Performance of MAO Coating on Ti5111 Alloy Surface of the Engine

In order to improve the tribological performance of the micro-arc oxidation coating on the surface of Ti5111 alloy engine, the co-existing deposition process was used and the W powder was diffused into the MAO coating by the action of high temperature.The results show that the thickness and surface roughness of MAO coating first increase linearly and then reach a relatively flat stage.After a small amount of W powder is added, melting and sintering occur, and the number of particles on the coating also decreases.When W powder content is 6 g/L,many small pores are obtained, and the number of pores decreases.Without W powder, there are mainly anatase, rutile, and titanium oxide in MAO coating.With the increase of W powder, the diffraction peak intensity of the W phase increases.When a small amount of W powder is added, the friction coefficient decreases relative to the matrix sample.When W powder content is 6 g/L,the friction coefficient is about 14% lower than that of the original MAO coating.The MAO coating produced without W powder appears mechanical engagement and has obvious plastic deformation.When a small amount of W powder is added, a large amount of W powder falls off, which results in a higher wear rate and an obvious furrow effect.