凹凸棒石和硅灰石对PTFE摩擦磨损行为影响

Influence of Attapulgite and Wollastonite on the Friction and Wear Behavior of PTFE

将凹凸棒石与硅灰石以不同配比添加到聚四氟乙烯(PTFE)中,通过机械混合、冷压烧结的方式制成PTFE/凹凸棒石/硅灰石复合材料。采用X射线衍射、傅里叶变换红外光谱、同步热分析、邵氏硬度计、环块摩擦磨损试验机、光学显微镜、3D表面轮廓仪对复合材料的理化性能和摩擦学性能进行表征。结果表明,凹凸棒石与硅灰石的引入使得复合材料的结晶度和玻璃转化温度降低,硬度增加,同时磨损率显著降低,其中添加质量分数10%凹凸棒石与30%硅灰石的PTFE的复合材料的磨损率仅为4.1×10^(–6) mm^(3)/(N·m),较纯PTFE的磨损率降低了97.9%,减磨效果最好。研究表明,凹凸棒石与硅灰石的引入有助于在金属摩擦副表面形成转移膜,有效改善了对偶摩擦副的界面特征以及摩擦自适应性,是降低磨损率的主要原因。

Attapulgite and wollastonite are added to polytetrafluoroethylene(PTFE)in different proportions,and PTFE/Atta-pulgite/wollastonite composites were made by mechanical mixing and cold pressing sintering.X-ray diffraction,Fourier Transform infrared spectroscopy,tangent–defense and space center,Shore hardness tester,ring block friction and wear tester,optical micro-scope,3D surface profiler were used to characterize the physical and chemical properties and tribological properties of the composite material.The results show that the introduction of attapulgite and wollastonite reduces the crystallinity and glass transition tempera-ture of the composite material,increases the hardness,and significantly reduces the wear rate.The composite material of PTFE with 10%attapulgite and 30%wollastonite is added.The wear rate is only 4.1×10^(–6) mm^(3)/(N·m),which is 97.9%lower than that of pure PTFE,and the wear reduction effect is the best.The studies believe that the introduction of attapulgite and wollastonite helps to form a transfer film on the surface of the metal friction pair,which effectively improves the interface characteristics and friction adaptability of the friction pair,which is the main reason for reducing the wear rate.