碳纳米管改性聚四氟乙烯复合材料的摩擦磨损性能研究

评价了用不同含量碳纳米管(CNTs)改性聚四氟乙烯(PTFE)复合材料的力学性能,利用MM-200型摩擦磨损试验机研究了CNTs含量对PTFE复合材料摩擦磨损性能的影响,借助于扫描电子显微镜观察分析了试样磨损表面及磨屑形貌,并探讨其磨损机理.结果表明:CNTs能够提高PTFE复合材料的硬度和冲击强度,在本文研究范围内,当CNTs的质量分数为7%时,PTFE复合材料的力学性能最佳;CNTs能够增加PTFE复合材料的摩擦系数、降低其磨损量,当其质量分数为10%时,PTFE复合材料的耐磨损性能最佳.纤维状碳纳米管可以阻止PTFE带状结构的大面积破坏,以及在摩擦过程中于偶件表面能够形成转移膜并隔离复合材料与偶件的直接接触是其减摩耐磨作用的主要原因.

Dry Friction and Wear Properties of PTFE Composite Filled with Carbon Nano Tubes

Effects of carbon nano tubes(CNTs) on friction and wear properties of polytetrafluoroethylene (PTFE) wear investigated using an MM-200 wear tester. Mechanical performances of PTFE composites were measured. Experimental results showed that CNTs could reduce wear and increase friction coefficient of PTFE. Furthermore, it could also increase hardness and impact intensity of PTFE. When content of CNTs is 7% in weight, mechanics performance of PTFE composite is optimal and when content is 10% in weight, the wear performance of PTFE composite is optimal. Worn surfaces of CNTs-filled PTFE composites and the shapes of the transfer film and worn debris were observed using a scanning electron microscope and an optical microscope. The reasons the wear of PTFE is decreased are probably that fibers in CNTs resisted severe mangle of PTFE strip structure, and that films transferred from counterpart surface prevented direct contact between PTFE composite and steel ring.