Abstract
This study investigates the micromechanical and microgalvanic dissolution behavior of cold-sprayed Cantor alloy–Cu mixed-metal coatings. Coatings with Cu contents of 20 and 63 vol.% were successfully deposited on the stainless-steel substrate using a process gas temperature of 800 °C and a gas pressure of 4.9 MPa. Electron channeling contrast imaging, combined with high-resolution scanning electron microscopy, revealed linear features in the coating microstructure that resemble deformation (mechanical) twins. Nanoindentation results represents the local mechanical properties of different microstructural regions in the Cantor alloy and mixed-metal coatings. Scanning kelvin probe force microscopy demonstrated that changes in Cu loading exert limited influence on the formation mode and electrochemical characteristics of Cantor alloy–Cu micro-galvanic couples. Electrochemical measurements showed that, as Cu ratio in mixed-metal coatings changed, the total Cu dissolution rate was governed mainly by the number of micro-galvanic cells. Overall, these findings provide mechanistic insight into mechanical and corrosion behavior of mixed-metal coatings. This knowledge can be leveraged to design environmentally friendly and highly effective anti-biofouling coatings for marine applications by adjusting the Cu content.