Characterisation of electrodeposited Ni–Zr coatings prepared at different current densities

Abstract

In this work, Zr particles reinforced Ni–Zr composite coatings were prepared by eletrodeposition from a Watts bath at different current densities. The effects of current density on the surface morphology, composition, texture, grain size, microstrain, hardness, residual stresses and corrosion resistance of the composite coatings were investigated in detail. The results showed that the Zr particle contents in the coatings increased with reducing current densities and have an effect on the microstructures and the properties of the composite coatings. As the current densities decreased, the (200) preferred orientation of the coating changed to the random orientation or the slight (111) preferred orientation and the grain size decreased. The residual stress and hardness of the composite coatings increased with reducing current densities. The corrosion resistance of coatings increased with reducing current densities and attained the best corrosion resistance at 2 A dm⁻².

Keywords:

• Ni–Zr composite coating
• Electrodeposition
• Texture
• Residual stress
• X-ray photoelectron spectroscopy
• Corrosion resistance