Entstehung von Sulfatnestern im Rost bei der atmosphärischen Korrosion von Stahl I

Occurrence of sulphate nests in rust during the atmospheric corrosion of steel. I. A pure FeSO₄, solution (with ³⁵S) was used to generate, on steel surfaces, a continuous layer of FeSO₄, through evaporation. The samples thus treated were exposed to the action of air of different humidity. Within three hours, the sulphate ions tend to concentrate on the surface of the sample and to penetrate into the metal locally, causing nest-like concentrations of corrosion products. The number of the nests increases with the FeSO₄, concentration up to a maximum. Between the frequency and the size of the nests, there is a correlation which depends on air humidity. With increasing air humidity, the size of the nests increases whilst their number decreases.