PAO3基磁性流体的摩擦学性能研究

制备了以Fe3O4为磁性纳米粒子的航空基础油(PAO3)基磁性液体，通过X射线透射仪(XRD)、场透射电镜(TEM)、震动磁强计(VSM)和静置试验对其进行表征，并将其作为润滑油进行研究. 与基础油PAO3进行对比，共同考察了在不同摩擦对偶上的摩擦学性能. 通过扫描电子显微镜(SEM)、能谱仪(EDS)、轮廓仪和光学显微镜，测试了其在12CrNi4A钢/304钢、12CrNi4A钢/GCr15钢和12CrNi4A钢/Si3N4陶瓷摩擦副上的摩擦学性能，探究了其润滑机理. 结果表明：所制备的磁性液体能够稳定分散，满足磁性液体标准. 相比于基础油，磁性液体的摩擦学性能受到多因素的影响，在一定条件下具有优异的减摩和抗磨性能. 这主要归因于纳米Fe3O4粒子对摩擦副表面氧化膜的去除与修复以及浓度和磁场对其分散性与团聚性的影响.

A magnetic fluid based on aviation base oil (PAO3) with Fe₃O₄ as magnetic nanoparticles was prepared. The as-prepared sample was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM) and static stability test, and then evaluated as a lubricant. Its tribological properties on different friction pairs were comparatively investigated and compared with the base oil PAO3. Furthermore, the tribological performance of the magnetic fluid on three typical friction pairs, i.e., 12CrNi4A steel/304 steel, 12CrNi4A steel/GCr15 steel and 12CrNi4A steel/Si₃N₄ ceramic, was tested via scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), profilometer and optical microscope, and its lubrication mechanism was explored. The results demonstrate that the as-prepared magnetic fluid can disperse stably and complies with magnetic fluid standards. Compared with the base oil PAO3, the tribological properties of the magnetic fluid are influenced by multiple factors, and it exhibits excellent friction-reducing and anti-wear performance under specific conditions. This is mainly attributed to the removal and repair of the oxide film on the friction pair surfaces by the nano-sized Fe₃O₄ particles, as well as the effects of concentration and magnetic field on its dispersibility and agglomeration behavior.