Enhancing Copper Coatings with Graphene Nanoplatelets by Electrodeposition

Copper–graphene nanoplatelet (Cu–GNP) composite coatings were electrodeposited onto nickelplated steel substrates using direct current (DC) and pulse reverse current (PRC) techniques. The influence of the deposition regime on microstructure, nanoplatelet incorporation, and mechanical performance was investigated. Optical microscopy revealed that PRC deposition produced more homogeneous and refined microstructures compared to DC deposition. Raman spectroscopy confirmed the successful incorporation of graphene nanoplatelets within the copper matrix. Microhardness measurements showed a significant improvement in mechanical performance, with PRC coatings reaching an increase of 69.7% compared to DCdeposited coatings. The enhanced hardness is attributed to grain refinement, improved nanoplatelet dispersion, and effective dispersion strengthening mechanisms activated under pulse reverse conditions.