Abstract High performance polymer composites, (especially short fiber reinforced) have gained immense importance in the field of tribo-materials, especially for dry bearings. Among various key parameters controlling the final performance, the processing technique is the one, which is least investigated. Injection molding leads to a uniform dispersion and distribution of fibers but at the cost of an excessive reduction in the aspect ratio of fibers. Compression molding of short fibers retains their aspect ratio to a greater extent, but at the cost of inefficient dispersion of fibre strands. Interestingly, both the factors viz. High aspect ratio of fibers and excellent dispersion are important for deciding the performance of composites. In this work, two composites (Poly aryl ether ketone - 50 wt%, short glass fibres (length – 3 mm)– 30 wt % and synthetic graphite - 20 wt%) were molded by injection (I) and compression (C) molding. These were tribo-investigated in adhesive and abrasive wear modes in identical conditions. Based on thermal degradation of composites at 600 °C, the final fibre length was observed as 200–300 μm and 1.5 mm for I and C composites respectively. Both the composites showed low specific wear rate (K0) (~10-16 m3/Nm) and coefficient of friction (μ) (~0.03–0.05). Similarly, for abrasive wear, K0 and μ were observed ~10-10 m3/Nm and ~0.5–0.7 respectively. μ of I composite was lower in all conditions. The composite C was superior to the I in wear performance in adhesive wear, but not in abrasive wear. Worn surface analysis was done to understand the wear mechanisms.

中文翻译：

---

高性能聚合物复合材料 - 加工技术对纤维长度和性能的影响

摘要 高性能聚合物复合材料（尤其是短纤维增强材料）在摩擦材料领域，尤其是干式轴承领域具有重要意义。在控制最终性能的各种关键参数中，加工技术是研究最少的一个。注射成型导致纤维的均匀分散和分布，但代价是纤维纵横比的过度降低。短纤维的压缩成型在更大程度上保持了它们的纵横比，但代价是纤维束的分散效率低下。有趣的是，这两个因素即。纤维的高纵横比和优异的分散性对于决定复合材料的性能很重要。在这项工作中，两种复合材料（聚芳醚酮 - 50 wt%，短玻璃纤维（长度 – 3 mm）– 30 wt% 和合成石墨 – 20 wt%）通过注射 (I) 和压缩 (C) 成型。这些是在相同条件下以粘附和磨料磨损模式进行摩擦研究的。基于复合材料在 600 °C 下的热降解，观察到 I 和 C 复合材料的最终纤维长度分别为 200-300 μm 和 1.5 mm。两种复合材料都显示出低比磨损率 (K0) (~10-16 m3/Nm) 和摩擦系数 (μ) (~0.03-0.05)。同样，对于磨料磨损，观察到 K0 和 μ 分别为 ~10-10 m3/Nm 和 ~0.5-0.7。I 复合材料的 μ 在所有条件下都较低。复合材料C在粘着磨损方面的磨损性能优于I，但在磨粒磨损方面不优于I。进行磨损表面分析以了解磨损机制。