【摘要】 用热压成型法制备了纳米SiO2填充超高分子量聚乙烯(UHMWPE)复合材料,采用销-盘式摩擦磨损试验机考察了纳米粒子对复合材料摩擦磨损性能的影响,采用扫描电子显微镜观察了复合材料磨损表面形貌,并借助X射线能谱仪对试样磨损表面进行了微区分析。结果表明:纯UHMWPE磨损表面局部存在着大量的粘着变形和疲劳裂纹的特征,填充15%(质量分数)的纳米SiO2能较好地改善UHMWPE/nano-SiO2复合材料的摩擦磨损性能,其磨损表面只存在粘着撕裂现象,看不到疲劳裂纹特征。当填充纳米SiO2质量分数达到20%时,其磨损表面存在贫Si区和富Si区,同时磨损表面呈现出热裂纹迹象,复合材料的耐磨性能改善程度明显下降,并且摩擦因数出现了增大趋势。更多还原

【Abstract】 Ultra high molecular weight polyethylene（UHMWPE） based composites filled with nanometer SiO₂ were prepared by heat compression molding.The effects of nano-particulates on the tribological behavior of the composites were investigated on a pin-on-disc test rig.The worn surfaces of the composites were observed on a scanning electron microscope.The micro-constituent of the worn surfaces was analyzed by using X-ray diffraction.The results show that there is a great deal of cohesive deformation and fatigue crack on some parts of pure UHMWPE’s worn surfaces.The UHMWPE composites filled with 15%nano-SiO₂ record smaller friction coefficient and wear rate than pure UHMWPE,and there is only cohesive tearing characteristic on its worn surfaces,while the characteristic of fatigue crack disappears.When the mass fraction of SiO₂ is up to 20%,there are two zones on the worn surfaces,one is lack of Si,and the other is abundant in Si,and thermal crack is caused.The improvement degree of the composites’ wear-resisting properties drops obviously,and the friction factor presents an increasing trend.更多还原