Coatings, Films, and Treatments

The component materials of the joint should be cleaned, pretreated, and pruned prior to assembly in normal conditions. Where design or functional requirements preclude the use of dielectric separation, metallizing (sherardizing, galvanizing, electroplating, cladding, or metal spraying) with anodic metal 

When using metallic coating over the whole bimetallic assembly, the coating metal should be less noble than either of the component metals - or at least the cathodic one. Anodic films on aluminum-based alloys should be considered a part of the dielectric separation. 

as a coating of reinforcing rods and other steel embedded in concrete, helps to prevent or delay formation of rust on such reinforcement in a marine environment. 

For mobile joints, various combinations of metallizing and plastic coating can be used (e.g. nylon) instead of dielectric separation between dissimilar metals. 

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