Study on Galvanic Corrosion Behavior and Anticorrosion Design of 2A12/1Cr11Ni2W2MoV

The galvanic corrosion behavior of several 2A12/1Cr11Ni2W2MoV galvanic couples was studied by electrochemical method, acid salt spray test and periodic infiltration test. The surface morphology, element analysis and corrosion mechanism of the samples were analyzed by SEM and EDS, respectively. Based on the corrosion sensitivity and corrosion resistance of galvanic couples, a reasonable anti-corrosion scheme for the galvanic couple was designed. The results show that the electrochemical information can predict the corrosion sensitivity of galvanic couples, which can be used as a basis for material selection. Among all the galvanic couples, the couple of 2A12-SAA/CdP has the most significant corrosion sensitivity. Sulfuric acid anodization on the surface of 2A12 aluminum alloy can improve the corrosion resistance of the specimen and effectively reduce the galvanic corrosion rate. The corrosion mechanism is the result of the synergistic effect of galvanic and crevice corrosion. The protective effect of 2A12-SAA couple sprayed with corrosion inhibitor is obvious, which can effectively inhibit the galvanic corrosion.