【摘要】 镁基材料表面进行微弧氧化处理(MAO)制备的多孔结构的陶瓷涂层在干摩擦环境下的摩擦系数较高,本文采用微弧氧化结合非平衡磁控溅射技术在纯镁基体表面制备出了MAO/CrN复合涂层。通过扫描电镜、显微硬度测试、X射线衍射仪能谱、摩擦磨损实验等手段研究了复合涂层的形貌、成分及摩擦磨损性能。结果表明:MAO/CrN复合涂层相比单层的MAO涂层力学与摩擦性能得到显著提高,其中硬度升高48%,载荷为1 N时的平均摩擦系数降低32.3%,转速为700 r/min时,磨损率降低达到74%。CrN/MAO复合涂层与WC硬质合金球在干摩擦过程中,在表层CrN涂层被磨穿之前,复合涂层磨损形式以黏着磨损和疲劳磨损为主。在表层CrN涂层被磨穿MAO涂层未被磨穿前,复合涂层的磨损形式以三体磨粒磨损为主。更多还原

【Abstract】 The surfaces of Mg-substrate were modified by micro-arc oxidation( MAO) via chemical routeand with compact CrN coatings,grown byclosed field unbalanced magnetron sputtering. The impact of the surface modification conditions on the microstructures,phase-structures and tribological behavior of the MAO/CrN coatings was investigated with scanning electron microscopy,X-ray diffractionand conventional mechanical probes. The results show that the MAO/CrN coatings significantly outperform the MAO layers. For example,the MAO/CrN coatings increased the hardness by 48%,decreased the friction coefficient( at 1. 0 N load) by 32. 3% and reduced the wear rate by 74% at 700 r/min. In dry friction against WC balls,the adhesive and fatigue wear explained the wear mechanisms before wearing-out of the CrN layer; and after CrN layer vanished,the three-body abrasive wear dominated till MAO layer was worn out.更多还原