聚乙二醇/聚乙烯醇复合润滑膜对铝合金微弧氧化陶瓷层的润滑作用

Lubrication Effect of Polyethylene Glycol/Polyvinyl Alcohol CompositeLubrication Film on Micro-arc Oxidation Ceramic Layer ofAluminum Alloy Surface

微弧氧化(MAO)技术可明显改善铝合金的力学性能和表面性能,然而微弧氧化后的陶瓷层显示出较高的粗糙度,导致铝合金在摩擦过程中磨损较大。为改善铝合金抗磨性能,通过热压聚乙烯醇(PVA)和聚乙二醇(PEG)聚合物在铝合金微弧氧化后的陶瓷层表面制备一种具有优异润滑性能的复合膜,在不同频率、载荷和润滑条件下表征复合膜的润滑性能,并通过X射线衍射(XRD)和傅里叶变换红外(FTIR)分析复合膜的形成方式和润滑机制。结果表明:复合膜的摩擦因数仅为无膜时的1/4,具有良好的润滑性能;复合膜在干摩擦、油润滑以及高速工作条件下,都保持了良好的润滑特性,但在水环境下复合润滑膜会发生局部溶解,润滑性能较差;复合膜的网络结构和聚合物的自润滑特性共同起到了优异的润滑作用。

Micro-arc oxidation(MAO)technology can obviously improve the mechanical properties and surface properties of aluminum alloy.However,the ceramic layer obtained by MAO shows high roughness,which leads to great wear of aluminum alloy during friction.To improve the wear resistance of aluminum alloys,a composite film with excellent lubrication performance was prepared on the ceramic layer surface of aluminum alloy after MAO using hot pressed polyvinyl alcohol(PVA)and polyethylene glycol(PEG)polymers.The lubrication performance of the composite film was characterized under different frequencies,loads and lubrication conditions.X-ray diffraction(XRD)and Fourier transform infrared(FTIR)were used to analyze the formation mode and lubrication mechanism of the composite film.The results show that the composite film has good lubrication performance,and its friction coefficient is only 1/4 of that without the film.The composite film maintains good lubrication characteristics under dry friction,oil lubrication,and high-speed working conditions,but it will undergo local dissolution in water environment,resulting in poor lubrication performance.The network structure of the composite film and the self-lubricating characteristics of the polymer play an excellent lubricating role together.