Comparison of H-Cr single layer and Ni-P/H-Cr duplex coating

In this study, the Ni-P/H-Cr coating from substrate to surface was deposited on copper by electroless plating (Ni-P) and electrodeposition (H-Cr). The surface morphology and cross-section observations were analysed using scanning electron microscopy and optical microscopy. The results showed that the use of Ni-P layer as an undercoat before H-Cr coating the surface morphology has changed from a non-smooth state to a smooth state. In addition, the microcracks on the surface layer of H-Cr can be reduced. The loss of mass diagram and the worn surfaces indicated that using an Ni-P layer underneath the H-Cr layer increased the wear resistance.