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腐蚀科学与防护技术 2003
ANALYSIS ON RUSTS OF CARBON STEEL SUBJECTED TO 20~30 YEARS EXPOSURE IN SOUTH-EAST COASTAL ATMOSPHERE
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Abstract:
Iron rusts on body of amphibious vehicles after service for 20-30 years in south-east coastal atmospheres have been analyzed by means of x-ray diffraction,SEM and EPMA.It was found that the phase components of the rust were goethite,akageneite,lepidocrocite,maghemite,magnetite and alpha-iron,as well as a little of the so called green rust *(I).Chloride ion was detected in the rusts and the influence of chloride on the formation of the main iron oxides and ferric hydroxides was also analyzed.Several smaller pits lying in a larger pit and some islet-like dissipated iron particles in the rusts showed that the corrosion failure of carbon steel was due to uniform corrosion and pitting corrosion.