Microstructural and mechanical characterisation of electroplated nickel matrix composite coatings

Abstract

Metal matrix composite coatings reinforced with hard ceramic particles are attracting growing interest due to their promising mechanical properties. In the present work, a thick nickel coating, containing micrometric Silicon Carbide (SiC) particles, was electro-deposited on a steel substrate from a suspension of SiC in a Watts-type Ni-plating bath. The texture and microstructure of the coating were examined using electron backscatter diffraction combined with energy-dispersive spectroscopy for phase differentiation. The interfacial strength between the Ni matrix and the SiC particles was investigated by nanoscratch experiments. Grid nanoindentation technique coupled with an image correlation-based targeted indentation analysis and a statistical data treatment were employed to quantify mechanical properties of the composite and to map and extract mechanical properties and fractions of each phase. Additional investigation of the mechanical properties of the coating was performed using peak force quantitative nanomechanical mapping experiments.