The influence of cobalt on the corrosion resistance and electromagnetic shielding of electroless Ni–Co–P deposits on Al substrate

Electroless Ni–P and Ni–Co–P deposits were obtained on Al substrate. Their surface morphology, microstructure and composition were analyzed using SEM and XRD. Their corrosion resistance was characterized by anodic polarization curves. Based on the measurement of the thickness, electrical conductivity and magnetic conductivity of the deposits, their electromagnetic shielding effect values were calculated and the influence of cobalt on the corrosion and electromagnetic shielding properties of Ni–Co–P deposits was revealed. The results showed that cobalt improved the corrosion resistance and greatly enhanced the electromagnetic shielding property of Ni–Co–P deposits. Electroless Ni–Co–P deposits on Al substrate would impart the product with high corrosion resistance, good electromagnetic shielding effect and light weight.