二烷基二硫代磷酸铕的摩擦磨损性能研究

Study on the Tribological Behaviors of Europium Dialkyl dithiophosphate

将稀土化合物用作润滑油减摩抗磨添加剂是目前摩擦学研究的前沿课题之一。为了充分发挥我国稀土资源丰富这一优势，以稀土元素的摩擦学应用为出发点，对自行合成的油溶性二烷基二硫代磷酸铕的摩擦磨损性能进行了试验研究，同时还用扫描电子显微镜、Ｘ射线能谱仪、俄歇电子能谱仪和Ｘ射线光电子能谱仪进行了相应的摩擦化学研究，并与常用的二烷基二硫代磷酸锌的作了对比．结果表明，二烷基二硫代磷酸铕的减摩抗磨性能比二烷基二硫代磷酸锌的好，主要原因是其在摩擦过程中发生摩擦化学反应形成了由Ｅｕ２Ｏ３、ＦｅＳ、有机硫化物、硫酸盐和磷酸盐等组成的边界润滑膜，而且稀土元素铕在摩擦界面向钢基体渗透而改变了表层的裂纹扩展抗力和表面压应力，这也是二烷基二硫代磷酸铕呈现出良好减摩抗磨性能的重要原因．

The study of rare earth compounds as lubricant additives has become one of the mostinterested research topics for tribochemists,To give full play to the superiority of China'S rich rareearth resources,extensive studies of tribological application of rare metallic compounds have beenconducted.In this paper,the tribOlogical performance of oil soluble europium dialkyldithiophosphate(EuDDP)was evaluated and compared with commercial zinc dialkyldithiophosphate(ZDDP). Thereafter,the tribochemical features of EuDDP were studied through scanning electron microscopy(SEM),energy dispersion analysis of X-ray(EDX),Auger electron spectroscope(AES)and X-ray photoelectron spectroscopy(XPS).The results indicated that EuDDP possesses better lubricationability than ZDDP,This can minly be attributed to the formation of a boundary film containingEu2O3,FeS,organo-sulfide,sulphate,phosphate, etc,and a europium-rich diffused layer whichchanged the critical stress for surface crack to occur.