MIL STD- Dissimilar Metals (Notice 3)

5.1.2 Table II list metals in the order of their relative activity in sea water environment. The list begins with the more active (anodic) metal and procedes down to the least active (cathodic) metal of the galvanic series. A 'galvanic series' applies to a particular electrolyte solution, hence for each specific solution which is expected to be encountered for actual use, a different order or series will ensue. Galvanic series relationships are useful as a guide for selecting metals to be joined, will help the selection of metals having minimal tendency to interact galvanically, or will indicate the need or degree of protection to be applied to lessen the expected potential interactions. Generally, the closer one metal is to another in the series, the more compatible they will be, i.e. the galvanic effects will be minimal; conversely, the farther one metal is from another, the greater will be the effect. In a galvanic couples, the metal higher in the series represents the anode, and will corrode preferentially in the environment.