the action of electropositive and electronegative metals due to the wasting away of the positive metal. This is most noted when iron (Fe) and brass, copper (Cu), or copper (Cu) and zinc (Zn), are in contact in the presence of acid-diluted water.
Flow of electrons which occurs when two dissimilar metals come into contract in the presence of moisture which is capable of carrying electric currents, resulting in the corrosion of the more active metal, which is lower on the galvanic scale, without damage to the more passive metal.
When iron and steel are subject to conditions of aqueous corrosion the incidence and rate at which the corrosion takes place will alter if the steel is coupled with other metals or alloys that are also exposed to the electrolyte. Copper, brass, bronze, lead and nickel are more "noble" and act as auxiliary cathodes to the steel and accelerate its anodic dissolution, that is, its corrosion. Magnesium, zinc and zinc-base alloy are nearly always less noble and tend to divert the attack from the steel to themselves. The galvanic relationship of various metals is an important factor affecting corrosion.
The corroding action of two unlike metals due to electrical current passing between them.
If two unlike metals are immersed in an electrolyte an electrical current will flow. The metal, which becomes the anode of this cell will corrode and dissolve, while the other metal, the cathode will be protected from corrosion. The two metals do not have to be vastly different for this effect to take place. It can occur with, say, copper and copper alloy. It can even occur with two different parts of the same sheet, tube or rod. The purpose of the sacrificial anode in Dux water heaters is to provide a metal (magnesium or aluminium) more reactive than the steel, brass or copper of the tank, element or valves for the corrosive effects of galvanic action to concentrate. That is, by providing an anode all other metallic components of the product become cathodes and are protected from corrosion.
A reaction which takes place that weakens the strength of metals when two incompatible metals are placed together.
A reaction between different metals in the presence of an electrolyte.
The phenomenon of corrosion of an anode (positive terminal - like on a battery). When two dissimilar metals are immersed in an electrolyte, an electrical potential will exist between them. If the two are in an electrical contact, a current will flow. The metal that becomes the anode (negative) of this cell will corrode and dissolve while the cathode (positive) will be protected from corrosion.
An electrochemical action that generates electrical current between two metals of dissimilar electrode potential. Galvanized steel: Steel coated with zinc for corrosion resistance.
An electroylic reaction between dissimilar metals in the presence of an electrolyte.
An electrical process by which corrosive elements are leached from one metal substance and attracted to another.
