A new magnesium anode with high efficiency for cathodic protection of steel in hot water was developed. The new anode is based on Mg-6%Al-3%Zn (AZ63) with the addition of Sr. The beneficial effect of Sr additions is the more negative potential and the reduced self corrosion of Mg-6%Al-3%Zn. The free corrosion potential of AZ63, as well as the potential under galvanostatic polarization, decreases with increasing strontium concentration. The minimum potential was determined at a strontium concentration of 1%. Furthermore, strontium influences the hydrogen development. The minimum hydrogen volume was determined at 1% Sr. The decreased hydrogen development is due to a reduced self corrosion of the Sr-containing AZ63 alloy. The reduced self corrosion will increase the life time of the anode.
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