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3026702 
Journal Article 
Fouling corrosion in aluminum heat exchangers 
Su Jingxin; Ma Minyu; Wang Tianjing; Guo Xiaomei; Hou Liguo; Wang Zhiping 
2015 
Yes 
Chinese Journal of Aeronautics
ISSN: 1000-9361 
28 
3 
954-960 
WOS:000357461000034 
Fouling deposits on aluminum heat exchanger reduce the heat transfer efficiency and cause corrosion to the apparatus. This study focuses on the corrosive behavior of aluminum coupons covered with a layer of artificial fouling in a humid atmosphere by their weight loss, Tafel plots, electrochemical impedance spectroscopy (EIS), and scanning electron microscope (SEM) observations. The results reveal that chloride is one of the major elements found in the fouling which damages the passive film and initiates corrosion. The galvanic corrosion between the metal and the adjacent carbon particles accelerates the corrosive process. Furthermore, the black carbon favors the moisture uptake, and gives the dissolved oxygen greater chance to migrate through the fouling layer and form a continuous diffusive path. The corrosion rate decreasing over time is conformed to electrochemistry measurements and can be verified by Faradays law. The EIS results indicate that the mechanism of corrosion can be interpreted by the pitting corrosion evolution mechanism, and that pitting was observed on the coupons by SEM after corrosive exposure. (C) 2015 Production and hosting by Elsevier Ltd. on behalf of CSAA & BUAA. 
Aluminum; EIS; Heat exchanger; Pitting corrosion; Tafel plots