纳米碳化硅填充环氧树脂复合材料的摩擦磨损特性

以提高环氧树脂的摩擦磨损性能为目的,研究了纳米碳化硅粒子填充环氧树脂复合材料的滑动干摩擦磨损特性,着重探讨纳米粒子表面接枝改性、纳米粒子含量、摩擦条件等对复合材料摩擦学性能的影响。通过对复合材料磨损表面的形貌分析,以及复合材料的热变形性能和表面硬度的测定,探讨了复合材料的磨损机理。结果表明,纳米碳化硅粒子能在很低的含量下提高环氧树脂耐磨性、并降低其摩擦系数,而经过接枝处理后的纳米碳化硅粒子填充复合材料的上述性能改善更为明显,耐磨性比环氧树脂提高近4倍,摩擦系数降低36%。这说明在SiC纳米粒子表面引入聚丙烯酰胺接枝链后,由于界面的强相互作用 ( 包括化学键合与链纠缠),有效地提高了复合材料的抵抗裂纹引发能力等性能,从而有利于改善其摩擦学性能。

TRIBOLOGICAL PROPERTIES OF NANOSIZED SILICON CARBIDE FILLED EPOXY COMPOSITES

To improve unlubricated sliding wear properties of Epoxy, nano-SiC particles were incorporated as fillers to fabricate composites. Effects of surface modification via graft polymerization, content of the nanoparticles and wear conditions were studied. Based on the morphological observation of the worn surfaces and characterization of heat distortion and surface microhardness of the composites, the possible wear mechanism was discussed. The results indicate that the addition of low loading SiC nanoparticles can significantly decrease the specific wear rate and frictional coefficient of Epoxy resin. Much lower wear rate and frictional coefficient of the composites were observed when surface modified nanoparticles were used. The specific wear rate of the composites is 4 times lower than that of unfilled Epoxy and the frictional coefficient is decreased by 36%. It means that the grafting polymer ((i.e). polyacrylamide) introduced onto the SiC nanoparticles enhanced the interfacial adhesion, leading to increase crack initiation resistance and improve tribological properties of the composites.