碳纤维和氟化钙协同提高PTFE摩擦学性能研究

聚合物复合材料由于其自润滑特性和化学稳定性高等优势，在汽车和装备领域运动机构的摩擦学设计中发挥着越来越重要的作用. 本研究系统考察了氟化钙(CaF2)颗粒的加入对聚四氟乙烯(PTFE)和碳纤维(CF)增强PTFE材料摩擦学性能的影响规律. 研究发现，在PTFE中添加CaF2颗粒可明显改善基体材料的抗磨性能. 尤其，与分别填充有CaF2陶瓷颗粒或CF的PTFE材料相比，同时填充CaF2和CF的PTFE多元复合材料的耐磨性能分别提高了11.1和2.47倍. CF与CaF2表现出显著的协同抗磨作用，同时该多元复合材料表现出极低的特征磨损率[8.9×10−7 mm3/(N·m)]和优异的自润滑性能. 通过多种表征手段深入分析了金属对偶表面生长转移膜的微观结构以及界面的物理化学反应和产物. 结果表明，PTFE发生摩擦化学反应并生成的羧酸基团，随后与CF研磨产生的石墨碳、破碎的CaF2以及其摩擦化学反应产物碳酸钙(CaCO3与CaO)在闪温和机械力作用下发生摩擦烧结，促使易剪切、高承载特性转移膜在金属对偶表面生长，大幅降低了PTFE复合材料的磨损. 研究结果为设计超低磨损的新型聚合物自润滑复合材料奠定了基础.

Polymer composites play an increasingly important role in the tribological design of moving components in the automotive and equipment manufacturing sectors due to their advantages including self-lubricating properties and high chemical stability. This study systematically investigates the effect of calcium fluoride (CaF₂) particle addition on the tribological properties of polytetrafluoroethylene (PTFE) and carbon fiber (CF)-reinforced PTFE materials. It is found that adding CaF₂ particles to PTFE can significantly improve the wear resistance of the matrix material. Notably, compared with PTFE materials filled with CaF₂ ceramic particles or CF alone, the multi-component PTFE composite co-filled with CaF₂ and CF exhibits 11.1-fold and 2.47-fold improvements in wear resistance, respectively. CF and CaF₂ demonstrate a significant synergistic anti-wear effect, while this multi-component composite exhibits an extremely low characteristic wear rate [8.9×10⁻⁷ mm³/(N·m)] and excellent self-lubricating performance. The microstructure of the transfer film formed on the metal counterface, as well as the interfacial physicochemical reactions and their products, were thoroughly analyzed via multiple characterization techniques. The results reveal that tribochemical reactions occur in PTFE to generate carboxylic acid groups, which subsequently undergo tribosintering with the graphitic carbon produced from CF grinding, broken CaF₂ particles, and their tribochemical reaction products calcium carbonate (CaCO₃) and calcium oxide (CaO) under flash temperature and mechanical loading. This process promotes the growth of easily shearable, high-load-bearing transfer films on the metal counterface, greatly reducing the wear of PTFE-based composites. The findings of this study lay a solid foundation for the design of novel polymer self-lubricating composites with ultra-low wear.

搜集汇总

背景与挑战

背景概述

该数据集聚焦于摩擦学研究，系统探讨了碳纤维和氟化钙颗粒在协同作用下对PTFE复合材料摩擦学性能的增强效果，发现这种组合能显著提高材料的耐磨性和自润滑性能，并通过微观分析揭示了转移膜的形成机制。研究结果为设计新型超低磨损聚合物自润滑材料提供了重要基础。