W-20Cu复合材料的摩擦学性能研究

Research on Tribological Characteristics of W-20Cu Composite

在MPV-1500摩擦试验机上研究水热合成法制备的W-20Cu复合材料与铝合金在不同载荷条件下的摩擦磨损性能。结果表明:试样在900℃退火2 h,晶粒有明显的层错条纹,可形成屏障阻碍位错的运动,使位错湮灭困难,亚晶界或晶界增加,导致晶粒细化,材料硬度提高。随着载荷的增大,摩擦因数先增大后减小,稳定性总体较好;磨损量先增加后逐渐趋于稳定。载荷较小时,W-20Cu复合材料磨损面黏附较厚的高含Al层,磨屑呈片状,磨损机制主要为疲劳磨损;随着载荷的增加,黏附层变薄,磨屑呈细小的碎片状及粒状,磨损机制主要为黏着和轻微的氧化磨损。

The friction and wear properties of W-20 Cu composite prepared by hydrothermal synthesis method with Al alloy at different loading condition were researched on MPV-1500 friction tester. The results show that the grains have obvious stacking stripes fault when the samples are annealed at 900 ℃ for 2 h. The stacking fault forms a barrier, which can hinder the dislocations movement, and lead to difficult dislocation annihilation. Thus, the sub-grain boundaries or grain boundaries increase, eventually leading to a finer grain size and higher material hardness. With the increase of load, the friction coefficient increases firstly and then decreases, which has good stability generally. Then, the wear mass loss increases and gradually turns to be stable. When the load is small, the wear surface of W-20 Cu composite is adhered by the layers with high Al content, the wear debris are laminar, and the main wear mechanism is fatigue wear; with the increase of load, the adhesion layer is getting thinner, and the wear debris are in fine fragmentary and granularity, and the main wear mechanism is adhesive wear and slight oxidation wear.