边界润滑条件下机油污染物对摩擦学性能的影响

Effect of Contaminants on the Tribological Performances of Engine Oils During Boundary Lubrication Regime

选用Fe、Cu、Al、Pb、SiO_2固体颗粒作为机油污染物,在模拟的发动机缸套-活塞环往复运动实验台上,研究边界润滑条件下固体污染物含量和尺寸对机油摩擦学性能的影响。实验结果表明:机油中的固体颗粒物导致摩擦因数和摩擦功损失增加,同时增加摩擦副接触面的表面粗糙度;摩擦因数、摩擦功损失、磨损量均随污染物含量、颗粒物尺寸的增加而增加,其中铁粒子污染物影响最大,铜次之,铅的影响最小;固体颗粒物会降低发动机性能,增加燃油消耗,为降低固体颗粒物对机油的影响,必须提高机油过滤精度。

The solid particles of Fe,Cu,Al,Pb and SiO2 was selected as the contaminants in the engine oils,the effect on the tribological performances of the engine oils by the contaminants content and grain size was studied on the simulated sliding reciprocating motion test rig of the engine piston ring / cylinder liner during boundary lubrication regime. The results show that the presence of the solid contaminants in engine oils leads to an increase in friction coefficient,wear and frictional power losses,increasing the surfaces roughness as a consequence. The friction coefficient,wear and friction power losses are increased with the increasing of contaminants content and grain size. Iron and copper contaminants come first and second in ranking respectively,and this is followed by lead. The presence of the solid contaminants in engine oils impacts negatively on the performances of engine and increases fuel consumption,in order to minimize the effect of solid contaminants,it is necessary to improve the filtration accuracy for engine oils.