The impact of composite graphene/Ni coating on nanoindentation of Ni: Deformation mechanism

KA Krylova and LR Safina and YV Rusalev and JA Baimova, SURFACES AND INTERFACES, 61, 106093 (2025).

DOI: 10.1016/j.surfin.2025.106093

To improve the corrosion and wear resistance of the nickel surface, a protective graphene-based composite coating can be used. Electrodeposition can be used to cover the different metal surfaces with the composite nanocoatings for future application in various industries. Due to the structural transition that occurs at the nanoscale, it is difficult to analyze the reinforcement mechanisms experimentally. Graphene/Ni composite coatings of different thicknesses during nanoindentation are studied by molecular dynamics. Hardness and reduced Young's modulus are determined from the load/unload curves obtained from indenter displacement simulation. The results show that with the increase of the coating thickness hardness of the Ni substrate increases. A composite coating with a higher initial thickness has a higher resistance to indentation and can withstand high loads. Such a composite coating can be an effective protective coating against damage. For the coating thickness less than 2 nm, deformation strengthening occurred due to the dislocation activity in Ni. For greater thickness of the composite coating, strengthening occurred due to the rearrangement of the graphene network. At a composite coating thickness of 5.1 nm, the hardness of the Ni surface increases more than three times compared to Ni single crystal. The obtained results can provide a fundamental understanding for the application of graphene/Ni composite coatings and reveal the strengthening mechanisms under indentation based on nucleation and interaction of defects.

Return to Publications page