Corrosion of mild steel in water

Abstract

An apparatus is described for determining the corrosion behaviour of rotating metal specimens in test solutions having a range of oxygen concentrations. Long term tests (up to 150 days) have been carried out on steel specimens at temeratures between 5 and 90oC in triply-distilled water, solutions containing 35ppm chloride, Teddington tap water, and sea water. Oxygen concentrations have ranged from near deaerated to oxygen saturated. Corrosion behaviour can be broadly interpreted on the basis of competition between factors such as chloride and oxygen content of the test solutions and the presence of hardness salts.Increased chloride and oxygen content increased the mass loss of the specimens during the test period although a high concentration of oxygen in the absence of chloride ions passivated the surface of the steel. Hardness salts decreased the mass loss of the specimens.