镁铝和锌铝水滑石作为润滑油添加剂的摩擦性能和机理（英文）

Friction Properties and Mechanism of Mg/Al-and Zn/Al-Layered Double Hydroxides as Lubricant Additives

利用共沉淀法,合成了镁铝水滑石和锌铝水滑石。采用X射线粉末衍射、扫描电子显微镜和X射线荧光光谱对粉末进行了表征。利用四球摩擦磨损试验机对水滑石粉体作为润滑油固体添加剂的摩擦特性进行了测试。采用扫描电子显微镜和X射线光电子能谱对磨损表面进行了分析。结果表明:2种水滑石均具有典型的六方片层结构,晶粒尺寸在100～200nm之间。四球摩擦磨损试验中,2种水滑石润滑的磨损表面的主要元素化学态接近。锌铝水滑石与润滑油自身极压抗磨剂二烷基二硫代磷酸锌协同增效,提高了磨损表面Zn元素含量,其抗磨损特性明显优于镁铝水滑石。此外,锌铝水滑石也促进了摩擦副表面的氧化,减少了C元素的沉积。

The Mg/Al-and Zn/Al-layered double hydroxides(LDHs)as solid lubricant additives were synthesized by a coprecipittion method.The samples were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),and X-ray fluorescence(XRF).The friction properties of LDHs were determined by a four-ball friction tester,and the rubbed areas were analyzed by SEM and X-ray photoelectron spectroscopy(XPS).The results show that Mg/Al-and Zn/Al-LDHs both have a typical heagonal laminated structure and the grain diameters are in the range of 100–200 nm.The anti-wear properties of Zn/Al-LDHs are superior to those of Mg/Al-LDHs.The chemical states of main elements on the worn surface with Mg/Al-and Zn/Al-LDHs are similar.It is indicated that Zn/Al-LDHs have a synergistic effect with zinc dialkyl dithiophosphate on the increase of the Zn content for the improvement of the anti-wear properties,compared to Mg/Al-LDHs.Also,Zn/Al-LDHs promote the oxidation of metal surface and reduce the carbon content.