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Corrosion Aluminum

Any court, including wooden and plastic must have metal underwater parts. At least – it's mount and engine parts, as a maximum – the case of aluminum, which are very popular in our country for boats boats and yachts. But especially in freshwater and seawater metal parts of the vessel inevitably damaged by galvanic corrosion. And the installation of parts made of stainless steel does not guarantee long-term carefree swimming. The most dangerous so-called local corrosion, which occurs in small areas of the surface, usually very intense, and ends with the destruction of the hull or ship's equipment. But there is a simple solution – the use of anodes.

You do not need to know more school course in chemistry to understand why it is impossible to put the brass or copper fasteners in aluminum housing. In water or in moist air from two metals with different potentials, galvanic cells are formed, a sort of 'battery'. And the more potential difference in metal forming corrosion couple, the more intense destruction of the proceeds of one of them speaker the anode. What kind of metal in the pair will break down due to corrosion? For the answer to find the number of standard electrode potentials of metals. Anode metal will always be with less capacity. And I need it? – think you are, and will, in general, right. Sales to ships, we will meet only two types of anodes – aluminum and zinc. That is enough to answer the question: when to use zinc anodes, and when the aluminum? Aluminium Anodes are better than zinc, protects against corrosion, but also why and quickly destroyed.

The latter is not very important for fresh water, in which corrosion takes place less intensively. Therefore, aluminum anodes are recommended for vessels who attend predominantly in fresh waters. Zinc anodes recommend the use of salt or brackish water. Aluminum anodes are also in the salt water 'eaten up' too quickly. In vessels with fiberglass and wood buildings should be reserved only metal parts. In doing so they must be connected to the anode, either directly or through a copper cable. It should be noted anodes company Vetus. Vetus Zinc anodes are manufactured with the most high quality requirements of the metal (military technical standard of the USA). Otherwise, they are not effective enough. Aluminum anodes are made of aluminum Vetus-indium-zinc alloy. All anodes elaborate form, with a layer of paint on the inner side to protect the colored blocks. The choice of a special attachment comes in the form of rods to weld a steel hull, or special screws for fiberglass and wooden hulls. Anodes for the propeller shaft (axial anodes) are joined perfectly with the shaft and have a unique mounting system, so that work only on the outside.