Study on Corrosion Progress of Spheroidal Graphite Cast Iron in Atmospheric Environment

This study focused on the corrosion progress of spheroidal graphite cast iron in the atmospheric environment. The carbon steel and weathering steel were tested as comparative targets through atmospheric exposure. The corrosion rate of spheroidal graphite cast iron in four years is smaller than that of carbon steel, whereas equal to or less than that of weathering steel. As a result of investigating the density and corrosion resistance of the rust layer formed during the atmospheric exposure test, the rust layer of spheroidal graphite cast iron tends to have electrochemically high protection compared to carbon steel and weathering steel. This is consistent with the difference in time-dependent corrosion rate among three materials in the atmospheric exposure test. © 2021 Japan Society of Corrosion Engineering. All rights reserved.