Burhanettin İNEM, Kubilay KARACİF, Tülin KIYAK

Alüminyumun iletken polimer ile kaplanması ve kaplama mikroyapısına korozyonun etkisinin incelenmesi

Bu çalışmada, alüminyumun iletken polimer bir malzeme olan polianilin ile elektrokimyasal yöntemle kaplanması, kaplanan yüzeyin korozyon öncesi ve sonrası mikroyapısı incelenmiştir. Polianilin kaplama işlemi, okzalik asit çözeltisinde, iki farklı anilin konsantrasyonunda, potansiyel taraması yöntemi ile yapılmıştır. Kaplanmış yüzeyin elektrokimyasal incelemelerinde, bazı potansiyel değerlerinde, polimerin yükseltgenmesi nedeniyle anodik bir pik ve yine polimerin indirgenmesi nedeniyle katodik bir pik görülmüştür. Kaplama yüzeyinin mikroyapısı, optik mikroskop ve taramalı elektron mikroskobu (SEM) kullanılarak incelenmiştir. Kaplama işlemi sonrası mikroyapısal incelemelerde, iki farklı kaplama koşulunda da, polianilin kaplama filminin, alüminyum yüzeyini tamamen kapattığı, kaplamanın küresel ve karmaşık şekilli tanelerden oluştuğu görülmüştür. Uygulanan korozyon şartlarında, iletken polimer kaplamanın korozyona karşı kararlı ve dayanıklı olduğu belirlenmiştir.

Coating of aluminum with conducting polymer and investigation of the effect of corrosion on coating microstructure

In this study, electrocoating of polyaniline conducting polymer on aluminum and microstructure of coated surface were investigated before and after corrosion. The polyaniline coating was performed in oxalic acid solution by using cyclic voltammetry. During electrochemical investigation of coated surface, an anodic peak due to oxidation of polymer and a cathodic peak due to reduction of polymer were observed. Microstructure of coating surface was studied by using optical and scanning electron microscope (SEM). Microstructural investigation showed that polyaniline coating layer completely covered to aluminum surface and microstructure of polyaniline coating consisted of globular and complex grains structure for both conditions. Under the corrosion condition, the polyaniline coating was found to be stable and protective.

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