Tribological Properties of Polyalphaolefin (PAO6) Lubricant Modified with Particles Additives of Metallic Glass

In mechanical systems, friction and wear lead to energy loss and machine failure. Lubricants are widely used to minimize friction and wear between moving components. Additives in lubricants significantly improve the quality of the lubricants. In recent years, nanoparticles have started to play more important roles as lubricant additives because of their ability to minimize friction and wear reduction. Despite the advantages of nanoparticles as additives, there are also some challenges to their applications. The most significant challenge is that because of the strong van der Waals force, nanoparticles aggregate in solutions. In addition, their complex process of preparation and high costs limit application in large-scale fields. Metallic glasses (MGs) with long-range disorder structure exhibit novel physical and chemical properties, e.g., high strength and hardness, high elastic limitation, high hardness/elasticity ratio, which make them potentially suitable for use as additives for lubricants. This work presents the tribological properties of friction and wear behaviors of polyalphaolefin (PAO6) oil modified with Mn55Fe25P10B7C3 MG particles at different concentrations (0 similar to 0.5%, mass fraction). Four ball tests were performed with an MMW-1A tribotester, XRD was used to examine the structure of the prepared Mn-based powders, SEM was used to observe morphologies of Mn55Fe25P10B7C3 particles and worn surfaces; OM was used to measure the wear scar diameters (WSD) and its roughness was measured with a white light interferometer (WLI). The results show a significant decrease of up to 57.1% and 15.6% for the coefficient of friction (COF) and WSD, respectively, as the addition of 0.5% MG particles in PAO6. The addition of MG particles leads to a decrease of worn surface roughness. With a high hardness/elasticity ratio and similar modulus to the friction pairs, the MG particles show a "smearing-type" wear mechanism, thus enhancing the antifriction and antiwear performance of PAO6 lubricants.