Based on the regulation of joint microstructure, electrochemical impedance spectroscopy, kinetic potential polarization and immersion corrosion were used to comparatively analyze the differences in the electrochemical corrosion morphology and post-foil formation surface morphology of laser beam weld (LBW) sample and spin formed sample, and to compare the corrosion resistance and Cu foil-forming ability of two samples in H₂SO₄/NaCl solution and CuSO₄ reducing electrolyte. Results show that in H₂SO₄ and NaCl solutions, LBW sample and spin formed sample exhibit excellent passivation ability and corrosion resistance. Both samples show uniform corrosion morphologies and similar corrosion resistance in the strong acidic solution containing Cl^-. Meanwhile, the Cu foil formation ability of the welded joint is similar to that of the spin formed sample, and both samples obtain intact Cu foils with high-quality surfaces and small differences in properties.