Mechanical characterization of functional Cu-GnP composite coatings for lubricant applications

Composite coatings have increasingly been used to improve the wear resistance of materials or protect surfaces from wear. Graphene nanoplatelets (GnPs) allow exploiting both the carbon allotropes and nanomaterials properties to reduce friction. In this study, electrodeposition of Cu-GnP composite coatings was realized to improve the tribological behaviour of copper plates. Two grades of GnPs were exploited to produce self-lubricating coatings, investigating how the GnP size affects the tribological performance. The characterization was performed through profilometry and microscopy (SEM-EDS) to assess their morphology, in addition to wear tests to define the mechanical properties. The results proved that the dimensions of GnPs, which are width and thickness, greatly affect the morphological and tribological properties of the coatings.