The use of a galvanized steel core in magnesium and zinc anodes for cathodic protection is primarily to provide mechanical strength and durability to the anode.
Magnesium and zinc anodes are used as sacrificial anodes to protect metal structures, such as ships, offshore platforms, pipelines, and tanks, from corrosion. These anodes corrode preferentially to the metal structure they are protecting, which means that the anode material corrodes instead of the metal structure. This sacrificial corrosion process helps to prevent the metal structure from corroding, thus extending its lifespan.
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