表面改性钛合金与增强型聚四氟乙烯在海水中的摩擦学行为

Tribological Behavior of Surface-modified Titanium Alloy and Polytetrafluoroethylene-based Composites in Seawater

为改善海水环境中钛合金与增强型聚四氟乙烯摩擦副对磨时的摩擦学性能,采用离子渗氮、微弧氧化技术对Ti6Al4V钛合金表面进行改性处理。对比研究了Ti6Al4V合金基材与改性层在模拟海水环境中分别与两种增强型聚四氟乙烯配副材料对磨的摩擦学行为。结果表明:在海水介质环境中,Ti6Al4V钛合金及其表面渗氮、微弧氧化处理试样与两种增强型聚四氟乙烯配副对磨时摩擦系数均较低;Ti6Al4V钛合金基体不耐磨,且造成两种增强型聚四氟乙烯配副的严重磨损。上述两种表面处理均有效改善了钛合金表面的耐磨性能,其中表面离子渗氮处理钛合金耐磨性能更优,同时降低了增强型聚四氟乙烯配副的磨损程度,而微弧氧化处理则使增强型聚四氟乙烯配副的磨损加重。相同试验条件下,玻璃纤维增强聚四氟乙烯比锡青铜增强聚四氟乙烯的耐磨性能优。采用离子渗氮钛合金与玻璃纤维增强聚四氟乙烯组成配副材料应用于海水环境中服役的水压传动摩擦学元件有明显的优势。

In order to improve the wear （PTFE） composites in seawater, plasma resistance of Ti6Al4V alloy contacted with polytetrafluoroethylene-based nitriding （PN） and micro arc oxidation （MAO） were used to modify the surface of Ti6Al4V alloy. The tribological properties of Ti6Al4V alloy matrix and its modified layers sliding with polytetrafluoroethylene-based （PTFE） composites in seawater were comparatively investigated. The PTFE composites were made with glass fiber and bronze separately by compression molding. The results indicate that low friction coefficients were shown in the modified layers of Ti6Al4V alloy sliding with PTFE composites in seawater. The Ti6A14V alloy exhibits the poor wear resistance and leads to the serious wear of PTFE composites. The above two kinds of surface treatments effectively improve the wear resistance of Ti6Al4V alloy. The PN treatment with reducing the wear of PTFE composites shows the better wear resistance comparing with that via MAO treatment with accelerating the wear of PTFE composites. The glass fiber reinforced PTFE shows the better wear resistance comparing with that of the bronze reinforced PTFE in the same condition. It has obvious advantages that the titanium alloy with PN treatment contacted with glass fiber reinforced PTFE were chosen as the materials of the tribological components used in hydraulic transmission in the marine environment application.