The program of research covered by this paper was designed to determine the feasibility of the use of magnesium anodes for the cathodic protection of steel in sea water. Its principal objectives were the selection of the most suitable magnesium alloy for this service with respect to solution potential, freedom from polarization, and current efficiency, together with a study of the minimum current requirements of the steel cathode under varying conditions of exposure. The results obtained to date may be conveniently divided into two parts; the first dealing with the anodic performance of various magnesium alloys, and the latter with those reactions which take place at the cathode.
A study has been made of the anodic performance of a group of five magnesium alloys in sea water at the corrosion testing station at Kure Beach, N. C. The composition of these alloys is shown in Table I.
Standard 4...