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

Abstract

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.

Keywords:

• Hard chromium coating
• Multilayer coating
• Nickel phosphorus electroless
• Wear