Abstract

As environmental awareness continues to rise, research on water-based protic ionic liquids (PILs) and nanoparticle (NP) additives has become crucial in the field of green lubrication. This study designed two water-based PILs with different alkyl chain lengths and synthesized copper nanoparticles for their combination. The tribological tests showed that the synthesized PILs exhibited excellent friction-reducing and anti-wear properties. When PILs were combined with copper nanoparticles, the friction coefficient was further reduced by up to 85 %. The tribological performance was influenced by the structure of the alkyl chains. The combination of long chains PIL with copper nanoparticles showed a more pronounced effect, reducing the wear rate to 0.013 and achieving ultra-low friction. Through particle size and zeta potential analysis, we found that the dispersion stability of copper nanoparticles was significantly improved, with no significant aggregates forming even after 60 days of storage. This effectively addressed the agglomeration and sedimentation issues of nanoparticles, extending their lifespan as lubricant additives. This study confirms the synergistic optimization between PILs and copper nanoparticles, providing new insights into the use of nanoparticles as additives in water-based lubricants and expanding their potential applications in the lubrication field.

Keywords Plus：TRIBOLOGICAL PROPERTIES，MILD-STEEL，ADDITIVES，OIL，CU，CORROSION，PERFORMANCE，INHIBITORS，STABILITY，MECHANISM

Published in TRIBOLOGY INTERNATIONAL，Volume 202；10.1016/j.triboint.2024.110402，FEB 2025