磁场对含丁辛基二硫代磷酸锌润滑油的润滑增效作用

在四球摩擦磨损试验机的摩擦接触区域外加磁场，考察了有、无磁场作用下150SN基础油和含不同质量分数的丁辛基二硫代磷酸锌（T202） 润滑油的摩擦学特性。用扫描电子显微镜（SEM）和X射线光电子能谱仪（XPS）分析了磨斑的表面形貌和典型元素的化学状态，并讨论 了润滑机理。结果表明，磁场作用下含T202润滑油中钢球表面的磨斑直径及其摩擦系数均比无磁场时的小，且钢球表面的磨损程度与无 磁场时相比更轻微。XPS分析结果显示，含T202润滑油中的钢球表面形成了由FeSO4,FeS和ZnS等物质组成的摩擦化学反应膜，磁场作用 下钢球表面的O、S、Fe、Zn、P元素的相对原子含量均比无磁场时的高，从而推断磁场对含T202润滑油的润滑增效作用是磁场促进了摩擦化学反应膜的形成和磨损表面的改性引起的。

Improvement of Magnetic Field on Tribological Properties of Lubricating Oils With Zinc Butyloctyldithiophosphate

Tribological properties of 150 SN mineral oil and the oils doped with different contents of zinc butyloctyldithiophosphate(T202) under magnetic field or non-magnetic field were evaluated on a four-ball tribotester by applying an external magnetic field around the friction region. Moreover, the morphology and the tribochemical characteristics of worn surfaces were examined by a scanning electron microscope(SEM) and an X-ray photoelectron spectrometer(XPS). Then the lubrication mechanisms were discussed. The tribological test results indicated that the wear scar diameters(WSDs) of steel balls lubricated by the T202-containing lubricating oils and the friction coefficients of the corresponding oil under magnetic field were smaller than those without magnetic affection. The worn surface lubricated with the T202-formulated oils in a magnetic field was smoother than that obtained under the normal condition. Furthermore, the results of XPS analysis indicated that tribochemical films on the surfaces lubricated with T202-doped oils were mainly composed of compounds such as FeSO_4, FeS and ZnS. The atomic concentrations of oxygen, sulfur, iron, zinc and phosphorus species identified in T202 under magnetic field were higher than those without magnetic impact. It can be inferred that the improved anti-wear and friction-reducing ability of T202-doped oils was attributed to the promoted tribochemical reactions and the modification of the worn surfaces induced by magnetic field.