Abstract The present investigation aims to explore the influence of simultaneous loading of aramid/carbon fibers, as high-performance reinforcements, on thermal, mechanical, and frictional behaviors of phenolic-resin-based non-asbestos organic (NAO) friction materials. The hybrid composite specimens were made at different ratios of carbon and aramid fibers but at a total fixed fiber loading of 8 vol%. The influence of carbon fiber on the improvement of impact strength and thermal conductivity was found to be more prominent than aramid fiber. The thermal stability of friction composites under nitrogen and real condition was investigated. The frictional data drawn from a Chase type friction tester revealed that the coefficient of friction and fade behavior were improved by incorporating aramid fiber. However, carbon fiber improved the wear resistance significantly in comparison with aramid fiber. The surface morphology of the composites was investigated precisely using scanning electron microscopy. Taking all the characterizations (physical, thermal, and tribological) into account, it was revealed that the sample holding 6 vol% aramid fiber and 2 vol% carbon fiber presented the best performance in terms of coefficient of friction, wear rate and fade behavior.

中文翻译：

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混合碳-芳纶纤维对非石棉有机制动摩擦复合材料性能的影响

摘要 本研究旨在探讨同时加载芳纶/碳纤维作为高性能增强材料对酚醛树脂基非石棉有机 (NAO) 摩擦材料的热、机械和摩擦行为的影响。混合复合材料试样以不同比例的碳纤维和芳纶纤维制成，但总固定纤维负载量为 8 vol%。发现碳纤维对冲击强度和热导率的提高的影响比芳纶纤维更显着。研究了摩擦复合材料在氮气和真实条件下的热稳定性。从 Chase 型摩擦测试仪得出的摩擦数据表明，通过加入芳纶纤维，摩擦系数和褪色行为得到了改善。然而，与芳纶纤维相比，碳纤维显着提高了耐磨性。使用扫描电子显微镜精确地研究了复合材料的表面形貌。考虑到所有特性（物理、热和摩擦学），表明含有 6 vol% 芳纶纤维和 2 vol% 碳纤维的样品在摩擦系数、磨损率和褪色行为方面表现最佳。