CORROSION BEHAVIORS AND RELATIVITY OF HIGH STRENGTH ALUMINUM ALLOY IN DIFFERENT SIMULATED SO2 ENVIRONMENT

The corrosion behaviors of high strength aluminum alloy 7A04 in three different experimental conditions have been investigated by scanning electron microscope(SEM),energy dispersive X-ray detection (EDX),Fourier transform infrared(FTIR) and mass loss method,and the relativity has been analyged with the result of Jiangjin atmospheric environment.The results show that the corrosion product increases with testing hours prolonging,and the mass loss of corrosion product obeys the exponential rule as C=A·t~n.Surface observation shows that corrosion product is agglomerated and extended forth.The corrosion products are made up of alumina,aluminum sulfate hydrate and aluminum chloride.The simulation results for the aluminum alloy 7A04 at cyclic wet-heat conditions(40℃,8 h;25℃,16 h;95%RH) in the 0.067%SO_2 polluted environment had better correlation with Jiangjin exposure result according to the mass loss data in all simulation methods in the paper.