含MoDDP润滑油的氧化安定性及摩擦学性能研究

OXIDATION STABILITY AND TRIBOLOGICAL PROPERTIES OF LUBRICATING OIL WITH MoDDP ADDITIVE

采用压力差示扫描量热法(PDSC)、曲轴箱模拟试验、四球摩擦磨损试验考察了含添加剂二烷基二硫代磷酸钼(简称MoDDP)润滑油的氧化安定性及摩擦学性能,利用傅里叶变换红外光谱(FTIR)、原子发射光谱(ICP)、紫外荧光硫测定仪、扫描电子显微镜(SEM)和X射线能量色散谱(EDS)对曲轴箱模拟试验前后油样及其润滑钢球磨斑表面进行表征。结果表明:MoDDP具有良好的抗氧化性能,可有效提升油品初始氧化温度,降低曲轴箱模拟试验中油样的氧化程度;曲轴箱模拟试验中,MoDDP的加入使高温沉积物明显增多。沉积物元素分析结果显示,S,P,Mo等MoDDP特征元素是其重要组成;曲轴箱模拟试验后,油样润滑性能显著降低,结合油液元素分析及摩擦副表面分析认为,试验造成的液相中S,P,Mo元素的流失是其主要原因。

The PDSC, crankcase simulation test and four ball tests were employed to investigate the oxidation stability and triboligical properties of lubricating oil with MoDDP additive. The oil samples before and after the crank simulation test and the worn scar surfaces were characterized by FTIR, ICP, UV fluorescence sulfur determinator, SEM, and EDS techniques. The results show that MoDDP addi- tive has a good anti-oxidation ability that effectively enhances oil initial oxidation temperature and lower the oxidation extent of oil in the crankcase simulation test. It is found that the addition of MoDDP cause obvious deposits at high temperature in crankcase simulation test and that the triboligical properties of oil samples decrease significantly after crankcase simulation test. The element analysis indicates that the characteristic elements of MoDDP （S, P, Mo） are important components of deposits. The results of ele- ment analysis of oils and worn scar surfaces characterization suggest that the loss of element S, P, Mo in oil samples during test is the main reason.