添加石墨对热压法制备C/C复合材料摩擦磨损性能的影响

Effects of Graphites content on Friction and Wear Performances of C/C Composites Fabricated by Hot-pressing Process

以表面酚醛树脂包覆处理过的石墨颗粒,硝酸氧化处理的炭纤维和沥青为原料,经热压烧结制备短切炭纤维增强沥青基C/C复合材料。利用环-块磨损试验机对材料进行了摩擦磨损实验,借助SEM观察样品的磨痕和磨屑,研究了不同石墨含量对样品摩擦磨损性能的影响。结果表明,随着石墨含量的增多,样品的密度和弯曲强度逐渐提高,同时在摩擦磨损表面形成具有自润滑作用的摩擦膜,有利于降低磨损量,并保持摩擦系数的稳定。添加适量的石墨可获得摩擦磨损性能优良的C/C复合材料。

Using graphite particles coated by phenolic resin, carbon fibre oxidated by hot HNO3 and pitch as raw materials, short carbon fibre strengthened pitch based C/C composites were fabricated with hot-pressing process. Ring-bulk wear experiment was accomplished and grinding crack and grinding scraps were observed by SEM. The effects of graphites content on friction and wear performances of C/C composites had been studied in detail. The results show that, with the increasing of the graphite content, the density and flexural strength of the composites were improved gradually. The selflubricating film formed during wearing, which favorable to reduce the wear rate and stablige the friction coefficient. C/C composites with idea friction and wear performances can be fabricated by hot-pressing process when appropriate amount of graphite particles was added.