Structure and Properties of Ni-B/Graphene Oxide Composite Coatings Produced by Chemical Reduction Method

Abstract A nickel-boron (Ni-B)/graphene composite coatings were produced using chemical reduction method on a steel substrate. These composites were compared to Ni-B coatings without graphene embedded into the matrix. Graphene in the form of an aqueous suspension of graphene oxide flakes was used. Graphene was characterized by single-layered flakes about 0.5 µm in size. The coatings produced were characterized by an amorphous structure. The incorporation of graphene into the Ni-B matrix affects the surface topography and morphology of the coatings produced. The addition of graphene strengthened the coating material. An increase in the hardness (~ 1100 HK0.025) was noted for Ni-B/graphene composite coatings compared to the hardness (~ 950 HK0.025) of the Ni-B coatings without a built-in dispersion phase. Composite coatings also exhibited a better corrosion resistance than the coatings without embedded graphene.