The corrosion behaviour of 2 A12 aluminum alloy in marine environment was simulated based on the COMSOL. The results show that the pitting corrosion occurrs under the action of Cl

-

at the beginning of the corrosion. Subsequently

the corrosion is developed into intergranular corrosion at 175 h

and eventually evolved into comprehensive corrosion with the advance of the reaction

which is completely corroded at 280 h. However

the corrosion rate is significantly increased in model containing the IMP. The corrosion is developed into intergranular corrosion at 75 h

and finally evolved into comprehensive corrosion

which is completely corroded at 240 h. A large amount of Al（OH）

3

which is generated by electrochemical corrosion

is deposited on the surface of the pit

preventing the contact between electrolyte and substrate and thus inhibiting corrosion. Simulation results show that with prolonging corrosion time

the self-corrosion current density of 2 A12 alloy is decreased firstly and then increased until the corrosion is end.