Characterization of Cu-Ni multilayers coating by electroplating on carbon steel A106 grade C used for petroleum applications

Abstract

Low carbon steel is extensively employed industrial pipelines due to its low cost, and eases of welding, but its susceptibility to corrosion necessitates surface protection strategies such as: electroplating (ELP). In this study, multiple layers of copper (Cu) and nickel (Ni) are deposited on a low carbon steel type A106 grade C (St.A106-B) substrate using the (ELP) process. The samples are divided for coating into three groups: the first group is Ni coating layer, the second is Cu coating layer, and the third consisted of two layers, Cu and Ni. The experiments are conducted over three different electroplating periods: 10, 20, and 30 minutes (min.). The parameters, including the ELP time, are studied in the experiments. Measurement and tests methods are used , which included roughness, micro hardness testing, thickness measurement, and X-ray diffraction (XRD) analysis to describe the multilayers phases features compared to all obtained samples, also surface compositions of the electroplated layers are calculated using these methods. Results have been showed that surface roughness, thickness, and hardness increase, with increasing the ELP time. The obtained results indicate that increasing the electroplating time will lead to an increase in the thickness of the coating layer. On the other hand, increasing the electroplating time affected the increase in surface roughness of both Ni and Cu. The highest value of microhardness is achieved at the longest plating time in the Cu-Ni bilayer (30 min.). As for the XRD test results, consider as good evidence of the presence of Cu, Ni and Cu-Ni in both the inner and outer finishing layers, respectively.