镁基表面微弧氧化陶瓷膜的摩擦磨损特性

Friction and Wear Characteristics of Ceramic Film Produced on Magnesium Alloy by Micro-Arc Oxidation

摘要: 利用微弧氧化技术在AZ91D镁合金表层制备原位生长陶瓷膜，利用SEM、XRD等表征了镁基陶瓷膜，并研究了镁基陶瓷膜的摩擦磨损特性及磨损机理。结果表明，镁基陶瓷膜表面呈典型的微孔叠加多孔结构特征，其主要成分是Mg₂SiO₄、MgAl₂O₄、Mg₃(PO₄)₂、MgO，膜层与基体结合紧密，结合力为14~15 N。不同载荷和不同摩擦速度等因素对镁基陶瓷膜的磨损都有很大的影响。随着载荷和滑动速度的增大，陶瓷膜的磨损失重也明显增大。油摩擦的磨耗较小，其磨损机理主要为疲劳磨损，同时也附带磨粒磨损。干摩擦的磨耗较大，其磨损是由磨粒和疲劳磨损共同造成的。

Abstract: Ceramic film produced on magnesium alloy AZ91D was prepared by micro-arc oxidation. The morphology, phase composition and element distribution of ceramic membrane were tested by SEM, XRD. The growth process and characteristics of the film were analyzed. Then the friction and wear mechanism of coatings on magnesium alloy by micro-arc oxidation method were studied. The results showed that the main components of t coatings on magnesium alloy were Mg₂SiO₄, MgAl₂O₄, Mg₃(PO4)₂ and MgO. The film and the substrate are combined tightly with binding force 14 - 15 N. Factors such as different load and sliding wear speed have great influence on coatings of magnesium alloy by micro-arc oxidation. With the increase of load and sliding speed, the wear weight loss of ceramic coating is also obvious increase. Wear loss is smaller under oil friction condition, and its main wear mechanism is fatigue wear, with less abrasive wear. Wear loss is larger under dry friction condition, and its wear is caused by abrasive grain and fatigue wear together.