论文部分内容阅读
利用微弧氧化法在7475铝合金表面制备了微弧氧化膜,通过SEM、EDS对氧化膜表面-界面形貌、磨损形貌和化学元素组成进行分析,并用划痕法表征了氧化膜与基体的结合强度。通过摩擦试验考察了试样的磨损性能,测得了其在不同载荷作用下的摩擦系数曲线。结果表明,微弧氧化膜表面存在大量凹凸特征,主要元素为Al、O和Si,另含有其他合金元素和电解质残留元素,氧化膜与基体的结合强度为71.05 N;氧化膜磨损后表面Al含量有所增加,而Si含量呈现下降趋势,此时氧化膜已被磨穿,同时,O含量基本不变,说明磨损后基体表面发生氧化现象;干摩擦条件下氧化膜的摩擦系数为0.8左右,随载荷增大,摩擦系数降低,摩擦曲线稳定性增加;在载荷为10 N时磨损量最大,磨损机制为磨粒磨损和疲劳磨损。
The micro-arc oxidation film was prepared on the surface of 7475 aluminum alloy by micro-arc oxidation. The surface-interface morphology, wear morphology and chemical element composition of the oxide film were analyzed by SEM and EDS. The oxide film and matrix The bond strength. The abrasion performance of the sample was investigated by friction test and the friction coefficient curve under different load was measured. The results show that there are many irregularities on the surface of MAO film. The main elements are Al, O and Si, and other alloying elements and electrolyte residual elements, the bonding strength between the oxide film and the substrate is 71.05 N. The surface Al content While the content of Si shows a downward trend. At this time, the oxide film has been abraded, meanwhile, the content of O remains almost unchanged, indicating that the surface of the substrate undergoes oxidation phenomenon after abrading. The friction coefficient of oxide film under dry friction condition is about 0.8, With the increase of load, the friction coefficient decreases and the stability of friction curve increases. The wear amount is the largest when the load is 10 N, and the wear mechanism is abrasive wear and fatigue wear.