Lo­cal el­e­ment

A local element is a very small area corrosion element. This occurs in a humid environment when a more noble metal (cathode) meets a less noble metal (anode). Under the influence of moisture, local elements usually occur at the point of contact of the various metals and cause corrosion damage there. This is particularly the case in susceptible areas such as welds, rivets, screwed joints or areas with damaged coatings