Yanhong Li, TianTian Liu, Yujuan Zhang, Pingyu Zhang, Shengmao Zhang, Study on the tribological behaviors of copper nanoparticles in three kinds of commercially available lubricants. Industrial Lubrication and Tribology, 2018, 70 (3): 519-526.

The addition of Cu NPs as lubricant additives could reduce wear and increase load-carrying capacity of commercially available lubricants remarkably, indicating that Cu NPs have a good compatibility with the existing lubricant additives in commercially availablelubricants. So, Cu NPs are hopeful to be directly used in commercially available lubricants.