Iput, Galvanic attack is just field name for a type of corrosion know as Galvanic corrosion. What happens is two electro-chemically dissimiliar materials are brought into contact through an electrolyte creating a galvanic cell. The metal ions from one of the metals is transferred to the other through the electrolyte,creating a weak electrical current and the appearance of corrosion on the metal giving up the ions.
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saxon