Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (51권2호 87-94)

Evaluation of Corrosion and Cavitation Erosion Resistance of Sealed Aluminum Alloy after Anodizing Treatment in Seawater

양극산화 후 실링처리된 알루미늄 합금의 해수 내 내식성과 캐비테이션 침식 저항성 평가

박일초;이정형;한민수;김성종;
Park, Il-Cho;Lee, Jung-Hyung;Han, Min-Su;Kim, Seong-Jong;

목포해양대학교 기관시스템공학부;
Division of Marine Engineering, Mokpo National Maritime University;

DOI : 10.5695/JKISE.2018.51.2.87

Abstract

Various sealing techniques were applied to the anodized 5083 aluminum alloy for marine environment to reduce corrosion and cavitation erosion damage. Electrochemical experiments and cavitation erosion tests were conducted to evaluate the corrosion resistance and cavitation resistance of the anodic oxide film treated with sealing in natural seawater solution. Then, damaged surface morphology was analyzed by scanning electron microscope(SEM) and 3D microscope. As the results of the electrochemical experiments, it was observed that the surface damage of all the experimental conditions in the anodic polarization experiment was locally grown by the combination of crack and corrosion damage. In the Tafel analysis, the corrosion resistance of all sealing treatment conditions was improved compared to the anodizing. On the other hand, cavitation erosion tests showed that the anodizing and all the sealing treatment conditions generated local pit damage by cavitation erosion attack and grew to crater damage in the observation of damaged surface by SEM. Also, the weight loss and the surface damage depth measured with the experiment time presented that most of the sealing treatment conditions showed better cavitation erosion resistance than the anodizing, and they had an incubation period at the beginning of the experiment.

Keywords

Anodizing;Sealing treatment;Corrosion;Cavitation erosion;Seawater;Aluminum alloy;