Preparation of Ni–Co–Cu Ternary Alloy Coatings by the Low‐Cost Electrochemical Additive Manufacturing

Abstract

Herein, Ni-Co-Cu ternary alloy coating is prepared by electrochemical additive manufacturing. Using potential as a variable parameter, the morphology, organization phase, composition, and performance of the coating are analyzed. The results show that current density, coating structure, and chemical composition varies depending on the potential parameters. As the potential increases, the thickness of the coating increases (5-10 μm), and the content of Co and Cu decreases (Co: 32.5-16.3 wt%. Cu: 27.6-8.7 wt%). The coating has a distinct multilayer structure with a thickness of nanometers per layer. The Ni-Co-Cu coatings prepared herein are all FCC nanocrystalline structures (90-100 nm). In a 3.5 wt% NaCl solution, the corrosion resistance of the coating decreases with the increase of potential parameters. The Ni-Co-Cu coating prepared under the lower potential parameter (À2.5 V) has the smallest corrosion current (9.32 Â 10 À6 A cm À2 ) and higher polarization resistance (53 667 Ω cm 2 ).