Electrochemical Monitoring And Research Of Protection Methods On Aluminum Alloy/Organic Coating Interface Filiform Corrosion

This paper refers to a large number of domestic and foreign literatures on the basis ofactual production, primarily for the aluminum alloy material for using in the maritime climate.the using of electrochemical monitoring system (polarization curves and AC impedance)through a series of electrical parameters (capacitance, resistors, inductors, etc.) to obtain thecorrosion of this type of corrosion behavior of filamentous material can easily occur tomonitor and combination of enterprises to provide corrosion data obtained by conventionalmethods, the study of corrosion occurrence and development of dynamic law, and proposedcorrosion protection methods. The main contents and conclusions are as follows:6063aluminum alloy typical polyester/6063aluminum alloy coating profiles (provided)the preparation of the specimen as the object of study. The samples pretreatment includepickling immersion, alkaline immersion, and a combination of both, which mainly removesthe aluminum surface of the second phase particles, thus improving the corrosion resistance ofaluminum and inhibition of filiform corrosion.Filiform corrosion of aluminum alloy, aluminum alloy specimens of different surfacetreatment were prepared, using scanning electron microscopy (SEM) and surface morphologyanalysis; using the EDS to determines the composition of corrosion products and analyses thecomposition of the corrosion products.Electrochemical workstation, prepared by electrochemical detection system on thepre-6063aluminum alloy or a typical polyester/6063aluminum alloy coating profiles(corporate) specimen monitoring, including the measurement of polarization curves and ACimpedance to analyze the filiform corrosion of6063aluminum alloy coating under the law ofdevelopment, the polarization curves and AC impedance test, as well as differentpre-treatment, to study the impact of the different alloy content on the corrosion resistance ofaluminum alloy on the basis that: since the resistance value of the corrosion current size andfilm and aluminum alloy corrosion resistance, in order to study the law of development offiliform corrosion.By induction, the method of deductive reasoning on the filiform corrosionthermodynamics and kinetics to study the mechanism, and to establish the inhibition model. Alloy and coating interface filiform corrosion development, especially the Cu exceedsbid make aluminum alloy surface are more likely to develop filiform corrosion. So it isnecessary to consider the alloy elements on aluminum alloy filiform corrosion resistance ofinfluence degree when add alloy elements, titanium-zirconium system passivation film hassome corrosion effects. Alkaline pretreatment anti-corrosion has a better effect than the acidpretreatment, the mean of acid and alkali mixed processing in filiform corrosion inhibition hasthe best performance, corrosion current is lower before one to two orders of magnitude thanothers. However it make clear that different types of aluminum alloy filiform corrosionresistance of the corresponding optimal pretreatment way is also different.