Evaluation of the Morphology and Corrosion Behavior of Zn‐Based Coatings Deposited on Low Carbon Steel Using a Sustainable Energy Source

Green energy sources offer a significant opportunity to make metallurgical processes more sustainable. In this regard, concentrated solar energy can be used to modify metallic surfaces. In this study, a Zn‐22Al‐2Cu coating was applied to an A36 steel substrate using a Fresnel lens. The coating was formed through the addition of 5–15 layers of powder alloy over the steel substrate. The coating is composed of η ‐zinc‐rich phases and zinc oxides. The compactness and porosity depend on the amount of layers used. The adhesion of the coating is in the range of 2.5–4.5 MPa. Electrochemical tests indicate that the coating promotes the formation of a protective layer. This behavior is in accordance with the time constants determined by electrochemical impedance spectroscopy which show the presence of two time constants for the coated samples, indicating the protective response of the corrosion products. Then, the addition of 15 layers of Zn‐based alloy powder demonstrates the most optimal performance, as it promotes the formation of a compact layer that properly covers the substrate surface, increasing adhesion and corrosion resistance. The corrosion products were zinc oxides, hydrozincite, and iron corrosion products for the coated and blank samples, respectively.