硬脂酸吸附对轴承限量供油润滑影响^*

The friction torque and the film thickness of PAO10 (poly-α-olefin) and PAO10S (poly-α-olefin + 0.2% w/w stearic acid) are measured using a full-bearing test rig and a optical ball-on-ring oil film test rig under conditions of limited oil supply, respectively. The results show that with the increase of the rotational speed, the frictional torque of the bearing first decreases and then increases, and there is a critical rotational speed at the minimum frictional torque. When the speed is lower than the critical speed, the frictional torque of PAO10S decreases with the increase of the oil supply, and is much smaller than that of PAO10. The reduced friction torque of the bearing by the PAO10S can be attributed to the low shear strength of the stearic acid adsorption film, and more important is the improved oil supply at the inlet from the enhanced replenishment on the lubrication track by the low surface energy by the stearic acid adsorption. The lubrication status of the PAO10 and PAO10S can be divided into three zones by the interference measurement of the lubrication film thickness, and the friction torque of the full bearing is closely correlated to the load-carrying capacity of the lubrication films in the three zones.