Preparation and characterisation of the Ni–C composite coating electrodeposited with carbon sol

Abstract

This study prepared the Ni–C nanocomposite coating using the carbon sol-reinforced electroplating method. The proposed carbon sol was designed and fabricated via an electrochemical process. The carbon sol was characterized with zeta potential analysis and transmission electron microscope; we found the carbon nanoparticles with a size of ∼300 nm were homogenously dispersed in the electrolytes. We further observed the morphologies of the surface and cross-section of the Ni–C composite coatings. These coating samples were tested for their electrochemical and mechanical properties. The results showed the morphology of the coating surface was compact when adding 10 mL/L of carbon sol. Under this condition, a thick Ni–C coating was deposited on the substrate, attaining the best corrosion and mechanical performance among all tested groups. However, a high carbon sol addition negatively affected the coating performance, which may have resulted from nanoparticle aggregation and excessive hydrogen evolution during the electroplating process.

Keywords

• Ni–C
• Carbon sol
• Electroplating