The effect of pH value and different kinds of anions on the corrosion behavior of Cu/Al casting-rolled clad plates in the alkaline solution was evaluated by means of scanning electron microscopy （SEM）,energy dispersive spectroscopy （EDS）,X-ray diffraction （XRD）,weight loss analysis,3D confocal laser scanning microscopy （CLSM） and electrochemical test.Results show the corrosion mainly occurs on the aluminum side.The corrosion resistance of the Cu/Al decreases as the pH value increases.When pH≥12,the dissolution of the film layer is faster than the passivation process.The addition of Cl-ions reduces the corrosion resistance of the Cu/Al clad plates,which leads to pitting corrosion.The higher the concentration of Cl-ions,the more prone the pitting to occur.The addition of SO42-ions causes the denudation of the samples.The corrosion resistance of the Cu/Al is better in the alkaline solution containing NO3-ions than that in the solution containing Cl-ions or SO42-ions.When adding SO42-,NO3-and Cl-to the pure alkaline solution,the corrosion resistance of the Cu/Al clad plates decreases.
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