Preparation of passive Cu-Ni-Fe coating on low-carbon steel for improving corrosion resistance

► Cu-Ni-Fe alloy coating was prepared on low-carbon steel. ► A compact and uniform Cu-Ni-Fe alloy coating constituted of homogeneous γ-phases was prepared at 1000 °C ► The Cu-Ni-Fe alloy coating is passive and provides corrosion protection in alkaline solution.