凹凸棒土改性聚酰亚胺复合材料的摩擦磨损性能

Tribological Performance of Attapulgite Modified Polyimide Composites

采用原位聚合法制备凹凸棒土/聚酰亚胺纳米复合材料,考察纳米复合材料的力学性能及在干摩擦、水润滑和油润滑3种情况下的摩擦磨损性能,并利用扫描电子显微镜观察磨损表面形貌。结果表明:凹凸棒土质量分数为3%时,复合材料的拉伸强度最好,随着纳米颗粒含量的增加,复合材料的拉伸强度、断裂伸长率明显下降,而弹性模量一直呈现上升趋势;在干摩擦条件下,低含量的纳米颗粒有助于转移膜的形成,可以有效改善材料的摩擦性能;在水润滑下,由于水的溶胀和冷却作用,摩擦因数较干摩擦降低了一个数量级;在油润滑下,润滑油的流动性有助于纳米颗粒分布到整个摩擦表面,材料的摩擦因数及磨损率有明显降低,相比于干摩擦和水润滑的磨粒磨损,此时磨损机制以疲劳磨损为主。

Polyimide nanocomposites with different proportions of attapulgite were prepared by flavor to the polymerization. The mechanical properties and tribological performances of PI composites were investigated. The morphologies of worn surfaces of PI composites were observed on scanning electron microscope. The results show that the low content of nano attapulgite can improve the tensile strength and elongation at break of PI composites. Under dry friction condition, a lower content of nano attapulgite can help to form the transfer film, so the friction coefficient and wear rate of PI composites are reduced. Under water lubrication condition, because of the water swelling effect and the cooling action, the wear rate of PI composites is decreased obviously compared oil can help the distribution of nanoparticles rate of the PI composites are reduced. this dominant wear mechanism under to the behavior on dry friction. Under oil lubrication condition, the lubricating on the whole friction surface of composites, so the friction coefficient and wear Compared to the abrasive wear under dry friction and water lubrication conditions, oil lubrication condition is fatigue wear.