聚酰亚胺基复合材料磨合期的磨损行为

Wear Behavior of Polyimide Composites during Run-in Stage

以质量分数20%MoS2改性热塑性聚酰亚胺(TPI)复合材料作为研究对象,在改进后的MPX-2000型摩擦磨损试验机上对该复合材料的磨损量进行了测定;根据材料磨损率变化情况提出了磨合阶段的确定方法,建立磨合期的磨损过程模型;研究了对偶面粗糙度和载荷对磨合期磨损行为的影响,并结合扫描电子显微镜分析了其磨损机理。结果表明:随对偶面粗糙度和载荷的增大,复合材料的磨合时间不断延长;随载荷的增加,磨损率增大,当表面粗糙度为0.34μm时,其值相对较小,二者对磨合期磨损行为的影响方式不同,分别对第三体在接触面中的移动及形成过程具有明显作用;低载荷下主要为磨粒磨损,当载荷增加到0.75MPa后,出现明显的粘着磨损特征。

Thermoplastic polyimide （TPI） composites modified by 20wt% MoS2 were taken as research object and the wear loss was measured by improved MP-X2000 type tribo-tester. A new method, which could determine the run-in wear stage, was proposed on the basis of the wear loss variation. Accordingly, the model of wear process was set up. The effects of the couple roughness and loading on wear behavior during the run-in stage were also investigated and the wear mechanism was determined by SEM. The results show that the run-in stage was extended while increasing the couple roughness or loading. The wear rate increased with increasing the load, and was relative small when the surface roughness was 0. 34μm. Due to the different actions on material wear behavior, the third body formation and remove process were conducted by the couple roughness and loading respectively. The abrasion wear was the main factor during the low load and adhesion wear became more important while the load reached to 0. 75 MPa.