The use of anode materials in cathodic protection has long been taken seriously by metal anti-corrosion units, and the function and type of anodes are particularly important. In fact, anode materials are mostly used as sacrificial anodes in cathodic protection. So do you know what are the main explanation methods of sacrificial anodes? Do you know what are the main commonly used sacrificial anodes? The following is a detailed analysis. I hope everyone can use anode materials better!
1: Detailed method of sacrificial anode explanation
The sacrificial anode method cathodic protection of this type of active metal or alloy is called a sacrificial anode. It is the earliest electrochemical protection technology. As the current flows out, the anode is gradually consumed, so it is called a sacrificial anode. The anode material is consumed quickly, so there are certain requirements for its installation location and installation method. Common sacrificial anodes are: magnesium anode, magnesium alloy sacrificial anode, zinc anode, zinc alloy sacrificial anode, aluminum alloy sacrificial anode, etc. The anode is consumed and the protected metal structure is protected by the anode, so the auxiliary anode applies the anode current to form an erosion current, which is called a sacrificial anode.
2: Commonly used sacrificial anodes
Aluminum anodes have a very large electrochemical equivalent, and a unit mass of aluminum anode can generate more current. Zinc is the earliest sacrificial anode material used. The standard electrode potential of zinc is -0.762V. It is often used for ship corrosion protection. Since the effective potential difference between zinc anode and iron is not large, zinc anode has high current efficiency in seawater medium. Magnesium has a relatively high chemical activity, and its standard electrode potential is -2.37V. It is mainly used in forced current cathodic protection in soil or fresh water. Composite sacrificial anodes are made by casting or extruding the surface of zinc anodes to wrap magnesium alloys or aluminum alloy anodes with their surface. The service life of composite sacrificial anodes is better than that of magnesium anodes or aluminum anodes.