Although commonly known as “zincs,” sacrificial anodes also come in various alloys such as aluminum, magnesium, and zinc—though the latter is the most common. Each metal is specially designed to adapt different environments, but all sacrificial anodes are meant to serve one single purpose: to prevent and stop corrosion of underwater metals. These metals include propellers, rudderstocks, stainless-steel propeller shafts, and bronze through-hull fittings to mention a few. The sacrificial anode protects the metals, either directly or indirectly via the vessel’s bonding mechanism.
How Sacrificial Anodes Function to Prevent Marine Corrosion
In cathodic protection, pieces of metal (sacrificial anode) are joined electrically to the ship’s hull. The anodes are more reactive than the substance used for the ship’s systems and body. This allows the anodes to collide in place of the ship’s systems and body, ensuring the ship stays safe at all times when it’s offshore. Sacrificial anodes are also used in many other areas such as subsea structures, ballast, pipelines, dock gates and so on.
Advantages of Aluminum Sacrificial Anodes
Aluminum anodes have a wide range of benefits. First, they’re impervious to the calcareous coating menace, hence are best suited for use in seawater, brackish, and freshwater. Second, aluminum anodes add more of a punch as they usually last longer than zinc anodes of the same weight. And finally, they also provide a much effective, double protection layer than zinc most of the time. Much surprisingly, aluminum anodes are less expensive than zinc anodes and pose zero threat to the marine environment.
In summary, aluminum sacrificial anodes can be deployed effectively anywhere there are metal parts that are partially or fully submerged in seawater. This ensures the metal parts in those areas are protected against unpleasant marine corrosion that may be a great threat to marine vessels if left unsecured. When purchasing aluminum anodes, make sure to choose those that are high quality and meet rigorous military-specification standards. Aluminum anodes have an “A-24779” mark, so make sure to confirm this figure before placing any order to make your marine endeavors such an exciting experience.