Advanced Mg-Mn-Ca sacrificial anode materials for cathodic protection

Addition of calcium to the Mg-Mn sacrificial anodes enhanced the anode efficiency by promoting the uniformly distributed corrosion along the grain boundaries and increased the driving potential by intrinsic electronegative potential of α-Mg. The reason for the uniform intergranular corrosion is that Mg₂Ca precipitate (cathode) at grain boundaries is galvanically coupled to α-Mg matrix (anode). Larger anodic area limits the localized nature of the intergranular attack.