Novel environmental-friendly lubricating materials: Water-based PAI-graphite-LaF3 bonded solid lubricating coatings.

The purposes of the work are to fabricate novel environment-friendly water-based polyamide-imide (PAI)-graphite-LaF 3 bonded solid-lubricating coatings (BSLCs), and investigate the corresponding tribological properties and mechanisms. The experimental results reveal that the preparation of the water-based PAI-graphite-LaF 3 BSLCs has significantly reduced the usage of organic solvent. When the mass percent of nano-LaF 3 is 5 wt%, the water-based PAI-graphite-LaF 3 BSLCs exhibit superior mechanical and tribological properties, which are comparable to those of the reported organic-solvent-based BSLCs. The tribological mechanisms were systematically investigated concerning the failure mechanism, the tribological reactions and structural fluctuations of graphite. Unlabelled Image • Water-based PAI-graphite-LaF 3 coatings are green lubricating materials. • Tribological properties of water-based coatings are comparable to those of the reported organic-solvent coatings. • Tribological mechanisms of water-based coatings are systematically investigated. [ABSTRACT FROM AUTHOR]