coating. A phosphate
coating converts the metal substrate to a uniform, inert surface, which improves bonding, minimizes the spread of oxidation if the
coating is scratchedand improves the overall corrosion resistance of the final part. A conversion
coating can be iron, zinc, polycrystalline, chromate, or manganese phosphate film. They are developed on both ferrous (iron based) and non-ferrous surfaces (zinc,
aluminum, terne and manganese). Parts are subjected to an acidic bath and a chemical...
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