<p>Cu–Ni and Cu–Co–Ni superhydrophobic films were constructed on the surface of B10 copper–nickel alloy welded joints using a two-step process of electrodeposition and stearic acid modification. The chemical composition of the film surface was determined using surface characterization techniques. The corrosion resistance of the films was characterized using electrochemical impedance spectroscopy, potentiodynamic polarization, and scanning Kelvin probe microscopy at multiple scales. The thermal stability, mechanical stability, and self-cleaning properties of the films were also characterized. It was determined that the Cu–Co–Ni superhydrophobic film exhibited the best performance, with a static water contact angle of 159.3°, a roll-off angle of 2.3°, a charge transfer resistance 3300 times higher than the substrate, a self-corrosion current density nearly three orders of magnitude lower, and a surface Kelvin potential increase of 420&#xa0;mV. The film demonstrated good thermal stability, excellent mechanical stability, and outstanding self-cleaning properties. Combining with previous studies, it was found that Co elements in the film contribute to the formation of a uniform and dense film, Ni elements enhance the adhesion and corrosion resistance between the films, and the combination of Co and Ni elements promotes uniform surface potential and further improves the corrosion resistance and interfilm adhesion of the films.</p>