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• Waterborne PAI-graphite coatings are green lubricating materials. • Waterborne PAI-graphite coatings exhibit superior mechanical and tribological properties. • Tribological mechanisms of waterborne coatings were systematically investigated. • Tribological properties of waterborne coatings under different experimental conditions were explored. The purpose of this work is to fabricate novel green waterborne PAI-graphite bonded solid-lubricating coatings (BSLCs) with superior mechanical and tribological properties so as to replace the reported organic-solvent BSLCs to some extent, and further investigate the lubricating mechanisms. The work indicates that, the preparation of the waterborne PAI-graphite BSLCs have greatly reduced the utilization rate of organic solvents (without the usage of organic solvent). The basic physicochemical properties of the coatings have reached the corresponding level of the organic-solvent BSLCs. When the mass ratio of waterborne PAI resin and graphite is 1.2, the waterborne graphite-based BSLCs exhibit superior mechanical and tribological properties, which are comparable to those of the reported organic-solvent BSLCs. The variation of tribological properties of the waterborne PAI-graphite coatings under diversified applied loads and reciprocating frequencies were explored systematically for the sake of the better understanding of environmental adaptability of the waterborne PAI-graphite BSLCs. [ABSTRACT FROM AUTHOR]

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]

In the article, a novel and facile method for hydrophilic modification of nano-lanthanum trifluoride particles was designed, the experimental results reveal that the surface of the nano-lanthanum trifluoride are absorbed with cross-linked molecules via electrostatic attraction and hydrogen bonds to further improve the water-dispersion capacity of nano-lanthanum trifluoride. In addition, the modified nano-lanthanum trifluorides achieve nano-scale dispersion in water-based bonded solid lubricating coatings, and 5 wt.% of modified lanthanum trifluoride into coatings can greatly enhance the mechanical and tribological properties of water-based coatings, which are superior to that of organic-solvent based coatings. Furthermore, the modified lanthanum trifluoride for promoting the wear resistance of the coatings illustrates more significant compared to unmodified lanthanum trifluoride and lanthanum trifluoride wetted by acrylic surfactant. [ABSTRACT FROM AUTHOR]

A series of novel environmental friendly bonded solid lubricating composite coatings were prepared via facile paint spray method and by virtue of adjusting the proportion of the composition of the coating (PTFE, water-based polyamide-imide (PAI) and LaF 3 ). The experimental results suggested that the physical, chemical and tribological properties of the water-based PAI-PTFE bonded solid lubricating composite coating with 5 wt% LaF 3 are comparable to that of organic-solvent resin composite coatings, additionally, the preparation of water-based resin bonded solid lubricating coatings have greatly minimized usage of fossil fuel. Furthermore, the work also explored the variation laws of tribological properties of the coatings under different applied load and slipping frequency. [ABSTRACT FROM AUTHOR]

• Two kinds of aqueous PTFE based coatings are green lubricating materials. • The basic physicochemical properties of two aqueous PTFE based coatings are comparable to that of organic-solvent based coatings. • Aqueous PTFE-ADPs based coatings exhibit superior mechanical and tribological performances to that of PTFE-PPs based coatings. • Tribocorrosive properties and active mechanism under diversified environments are thoroughly investigated. In the paper, the two kinds of environment-friendly aqueous PTFE based bonded solid lubricating coatings were prepared via facial paint spraying method, significantly reducing the waste of organic solvents. The basic physicochemical properties of two kinds of aqueous PTFE based coatings are comparable to that of organic-solvent based coatings. In addition, the tribocorrosive properties and active mechanism of two kinds of aqueous PTFE based coatings were thoroughly investigated under diversified environments, and the results illustrate that aqueous PTFE-ADPs based coatings exhibit superior mechanical and tribological performances to that of PTFE-PPs based coatings, and the tribocorrosive properties of two PTFE based coatings show major variation under different environments, which provides valuable references for environmental adaptability of the aqueous PTFE-based coatings, and further promotes the development of bonded solid lubricating coatings toward the direction of low carbon and environmental protection. [ABSTRACT FROM AUTHOR]

• Aqueous PAI-MoS 2 -graphite bonded solid lubricating coatings are novel green lubricated materials. • Aqueous coating with the MRGM of 0.3 exhibits more excellent mechanical and tribological properties. • Tribological mechanisms of aqueous coatings are systematically investigated concerning the morphology, structure and chemical compositions of wear scars. In this paper, a series of the environmental-friendly aqueous PAI-MoS 2 -graphite bonded solid-lubricating coatings (BSLCs) are prepared depending on the design concept of the recombination of two-component lubricant and aqueous resin, and the mechanical strength and wear resistance of the coatings are deeply optimized by virtue of the synergy of the components of coatings. The experimental results demonstrate that the successful preparation of aqueous BSLCs greatly reduces the utilization of toxic organic solvents and is conducive to environmental protection and resource conservation. Doping an appropriate amount of graphite into the aqueous BSLCs is beneficial to maximize the promotion of the mechanical and tribological properties of the coating, and when the mass ratio of graphite to MoS 2 (MRGM) is 0.3, the mechanical strength, friction reduction and wear resistance of the coatings display the comparable level as that of the organic-solvent based BSLCs. Based on the analysis of the variations of the morphology, structure and chemical composition of the wear scars, the corresponding active mechanisms on the mechanical and tribological properties of the coating are investigated in depth. [ABSTRACT FROM AUTHOR]