Three Active Materials Used in Aluminum Alloy Sacrificial Anodes

Many metals immersed in an electrolyte (such as seawater) will generate a voltage. Aluminum Alloy Sacrificial Anode PriceWhen two dissimilar metals are in contact (electrically connected), they create a galvanic cell (like a battery), with the less noble metal forming the anode (such as a bronze propeller) and the more noble metal forming the cathode (a stainless steel shaft). Aluminum alloy provides more protection and lasts longer than zinc. It will continue to work in fresh water and can be safely used in salt water. Aluminum is a good anode for many applications. If you want to protect two metals, you need to connect a third metal that is more active than the first two. The metal (such as zinc) becomes the anode for the other metal and protects the cathode by corroding (giving up the metal) itself - hence the name sacrificial anode. The three active materials used in sacrificial anodes are zinc, aluminum and magnesium. They have different properties and uses. To provide protection, a possible feasible voltage difference is needed between the sacrificial anode and the metal to be protected. The important property is the current capacity of the anode material. The anode creates a voltage difference, which drives an electric current between the anode and the metal being protected and through the water. Just like having a larger battery, the more capacity you have, the longer it will last. Incidentally, for a particular anode, the current rate depends on the surface area of ​​the anode, and the life depends on the mass.