目的 顺应当前尽可能选用低黏度润滑油而满足节能减排的要求，进一步探讨离子液体作添加剂时的摩擦润滑机理。方法 选用低黏度的聚α烯烃（PAO-4和PAO-8）为基础油，以二烷基二硫代磷酸锌（ZDDP）和季膦盐油酸离子液体（IL）为添加剂，在四球试验机上分别测量了40、100 ℃下的摩擦系数，并对比磨斑直径，对磨损表面进行SEM和EDS分析。利用轮廓仪对磨斑表面进行三维扫描，并分析其表面粗糙度。结果 与基础油对比，离子液体有效降低了摩擦系数，而传统添加剂ZDDP则导致摩擦系数上升。在部分工况，尤其是高温环境下，离子液体和ZDDP均可有效降低磨损。EDS和表面粗糙度结果可推断：ZDDP和IL在摩擦表面产生了两种截然不同的摩擦反应膜。结论 离子液体可以明显改善基础油的摩擦学性能。ZDDP和IL产生的不同摩擦膜引起了摩擦性能的不同，二者的成膜机理值得进一步探讨。

The work aims to meet energy conservation requirements by selecting low viscosity lubricants as far as possible, and further explore friction and lubrication mechanism of ionic liquid as an additive. Low viscosity polyalphaolefin (PAO-4 and PAO-8) was chosen as base oil, and zinc dialkyl dithiophosphate (ZDDP) and quaternary phosphonium salts of oleic acid ionic liquid (IL) were chosen as additives. Friction coefficient was measured at 40 ℃ and 100 ℃, respectively on friction and wear four-ball tester. Diameter of wear scars was observed with a microscope and also compared, the surfaces of wear scars were analyzed with SEM and EDS. Surface 3D scanning and roughness analysis were completed with the aid of a contact roughness profiler. Compared with the base oil, ionic liquid can effectively reduce friction coefficient, while traditional additive ZDDP increases friction coefficient. In some working conditions especially in high temperature environment, both ionic liquid and ZDDP can effectively reduce wear. According to EDS and surface roughness analysis results, it can be concluded that ZDDP and IL produce two distinct kinds of friction reaction film on friction surface, thus causing differences in friction performance. Film forming mechanisms of the films are further discussed.