空心微珠-碳纤维共混改性聚酰亚胺复合材料的摩擦学性能

通过模压成型制备了碳纤维与空心微珠共混改性的聚酰亚胺复合材料, 采用MRH-3型摩擦磨损试验机研究了空心微珠含量、滑动速度及载荷对复合材料摩擦学性能的影响, 并对其磨损形貌及机制进行了分析。结果表明: 空心微珠-碳纤维/聚酰亚胺复合材料摩擦学性能优于其单独填充的聚酰亚胺基复合材料; 空心微珠含量对共混改性的复合材料摩擦系数影响不大, 但其磨损率随着空心微珠含量的增加先减小后增大; 15%空心微珠-10%碳纤维(质量分数)共混增强的复合材料的减摩耐磨性能最佳; 随着滑动速度提高, 空心微珠-碳纤维/聚酰亚胺复合材料的摩擦系数下降, 磨损率增大; 空心微珠-碳纤维/聚酰亚胺复合材料摩擦系数随着载荷增加先下降后上升, 而磨损率则随着载荷增加而增大; 空心微珠-碳纤维/聚酰亚胺的主要磨损机制在较低载荷时为磨粒磨损, 在较高载荷时为粘着磨损和磨粒磨损。

Tribological properties of cenosphere and carbon fiber reinforced polyimide composites

Polyimide (PI) composites reinforced by cenosphere and carbon fiber (CF) were prepared by compression molding. The effects of load, sliding speed and content of cenosphere on tribological performances of the composites were evaluated on MRH-3 ring-on-block wear tester, and the wear morphology and mechanism were also analyzed. The results show that carbon fiber and cenosphere have the synergistic effect on the tribological properties of cenosphere-carbon fiber/polyimide composites; the tribological properties of the composite filled by cenosphere and carbon fiber were superior than those filled by single incorporation of cenosphere or carbon fiber. The content of cenosphere has little impact on the friction coefficient of cenosphere-carbon fiber/polyimide composites, but the wear rate declines with the increase of load and then improves. The 15% cenosphere-10% carbon fiber(mass fraction)/polyimide composite exhibits the lowest friction coefficient and wear rate. As an increase of the sliding speed, the friction coefficient of the composites decreases and the wear rate increases. The friction coefficient of the composite declines with the increase of load and then rises, but the wear rate increases with the increase of load. It is found that the main wear mechanism of the cenosphere-carbon fiber/polyimide is abrasive wear in the case of lower load, and shifts to the adhesive wear and abrasion while under higher load.