Research progress of wear-resistant antifriction coating based on micro-arc oxidation technology

Light metal materials (aluminum, magnesium, titanium and their alloys) are widely used in aerospace, automotive electronics, marine engineering and other mechanical fields due to their excellent properties such as light weight, high specific strength, etc. However, their service life and use range are limited because of lively chemical properties, easy corrosion, low hardness and easy wear. In order to improve the corrosion resistance and tribological properties of the surface interface of lightweight materials, micro-arc oxidation has been widely used as an effective surface strengthening technology. The research status of micro-arc oxidation treatment on the surface of aluminum, magnesium, titanium and their alloys, and the use of composite technology to prepare wear-resistant and anti-friction composite coatings were summarized systematically. The composite technology was divided into three categories: the first was pre-treatment (mechanical pretreatment, preset film layer) + micro-arc oxidation; the second was micro-arc oxidation direct composite technology (friction reduction composite, anti-wear composite); and the third was micro-arc oxidation + post-treatment (polishing, remelting, solid lubricating surface coating). The preparation technology and precautions of three kinds of composite technologies were introduced. The influence on tribological performance of moving friction pair parts and its optimization direction were analyzed. Finally, the challenges of micro-arc oxidation ceramic coatings in the field of tribology were pointed out, and its development direction was prospected from the aspects of ceramic film structure design and preparation, strengthening of toughness, reduction of impact on the fatigue performance of the substrate, and friction lubrication mechanism. © 2020, Chongqing Wujiu Periodicals Press. All rights reserved.