Question

Galvanic action or corrosion occurs between dissimilar metals when sufficient moisture is present to carry an electrical charge. In the "galvanic series," metals are arranged from most "noble" (least reactive to corrosion), gold and platinum, to least noble (most reactive to corrosion), magnesium. Rank the following metals from most to least noble: Copper, steel, silver, nickel, aluminum, titanium and lead. At which end would you place graphite?

Answer

From most to least noble: Titanium, silver, nickel, copper, lead, steel, aluminum. Graphite, gold, and platinum are considered the most noble. The farther apart two metals are on the list, the greater the deterioration of the less noble one.