Effect of Aluminum by Magnetron Sputtering on the Micro-Arc Oxide Film Layer of Titanium Alloy

In order to study the effect of magnetron sputtering Al coating on the performance of micro-arc oxidation film, a layer of pure aluminum coating was first sputtered on the surface of TC4 titanium alloy, and then, a composite ceramic oxide film was prepared on the surface of TC4 titanium alloy using micro-arc oxidation (MAO) technology to improve the performance of the material and analyze its wear mechanism. The effects of magnetron sputtered Al coatings on the phase composition, surface morphology, elemental content and wear resistance of the micro-arc oxide composite film layers were characterized using a variety of assays. The results showed that new diffraction peaks of alpha- Al2O3 and gamma-Al2O3 phases appeared in the Al-MAO composite film layer. The hardness of the MAO film layer increased by 30% after magnetron sputtering Al coating, the thickness increased by 61%, the roughness Ra and Rz decreased by 77% and 74%, respectively, and the wear resistance improved significantly. The wear mechanisms of MAO film layer are fatigue wear, adhesive wear and abrasive wear, and the wear mechanisms of Al-MAO film layer are abrasive wear and adhesive wear.