无机纳米微粒及聚四氟乙烯填充聚醚醚酮复合材料的摩擦学性能

Tribological Behavior of Inorganic Nano-Particulates and Polytetrafluoroethylene Filled Polyetheretherketone Composites

以纳米Al2O3、纳米TiO2及聚四氟乙烯(PTFE)作为复合填料,利用热压成型方法分别制备了纳米Al2O3-PTFE及纳米TiO2-PTFE填充聚醚醚酮(PEEK)复合材料;采用销-盘式摩擦磨损试验机考察了纳米微粒对复合材料摩擦学性能的影响;采用扫描电子显微镜观察分析了复合材料磨损表面形貌.结果表明:纳米微粒和PTFE作为复合填料可以显著改善PEEK的摩擦学性能,其改善效果同纳米微粒的填充量相关;当纳米填料的质量分数相同时,PEEK/PTFE/nano-TiO2复合材料的摩擦磨损性能明显优于PEEK/PTFE/nano-Al2O3复合材料;含纳米Al2O3的复合材料磨损表面呈现严重塑性变形特征,且塑性变形程度随纳米微粒含量增加而增大,而含纳米TiO2的复合材料磨损表面塑性变形轻微.

The polyetheretherketone (PEEK) based composites filled with nanometer Al_2O_3 or nanometer TiO_2 and polytetrafluoroethylene (PTFE) were prepared by heat compression molding. The influence of the inorganic nano-particulates on the tribological behavior of the composites was investigated on a pin-on-disc test rig, by dry sliding against AISI 1020 carbon steel disc in a pin-on-disc configuration. The worn surfaces of the composites were observed on a scanning electron microscope. It was found that the PEEK composites filled with the nano-particulates of a proper mass fraction and with 10%PTFE recorded smaller friction coefficients and wear rates than the PEEK-based composite filled with 10%PTFE alone. The nanometer TiO_2 as the filler was superior to the nanometer Al_2O_3 in terms of the ability to improve the friction and wear behavior of the PEEK-based composites. This was attributed to the enhanced plastic deformation of the PEEK-based composites in the presence of the Al_2O_3 nano-particulates, which was not observed for the PEEK/10%PTFE/5%nano-TiO_2 and PEEK/10%PTFE/7%nano-TiO_2 composites. It was suggested to pursue further work so as to reach a better understand of the differences in the tribological behaviors and wear mechanisms incorporated with PTFE and different types of inorganic nano-particulates.