Comparative Evaluation of Cold-Sprayed and Electroplated Copper Coatings: Enhanced Performance Characteristics and an Alternative Copper Coating Approach

To clarify performance differences between cold-sprayed copper coatings (CS-Cu) and electroplated copper coatings (EP-Cu), and optimize the cold spray process for efficient fabrication of high-performance Cu coatings, this study investigated the effects of spray gas temperature/pressure, spray distance, and gun traverse speed on the microstructure and properties of CS-Cu on AA6061 substrate via orthogonal experiments, and systematically compared the optimized CS-Cu with the EP-Cu. Optimization results showed that CS-Cu at specific parameters achieved optimal comprehensive performance, featuring low porosity, high hardness, and strong bonding strength. Microstructurally, CS-Cu was thicker and denser than EP-Cu, and was free of obvious interfacial. Mechanically, CS-Cu outperformed EP-Cu in elastic modulus and hardness. Wear tests revealed that CS-Cu had a lower steady-state friction coefficient and smaller wear volume (dominant abrasive wear), whereas EP-Cu exhibited inferior wear resistance and complex mechanisms due to weak interfacial bonding. CS-Cu also exhibited superior corrosion resistance, characterized by a self-corrosion current density of approximately 44% that of EP-Cu. In conclusion, optimized cold spray parameters produce dense, high-performance Cu coatings offering theoretical and experimental support for replacing electroplating in high-performance coating fabrication.