Reasons for Duplex Coating

There are seven good reasons to paint or powder coat hot-dip galvanized steel: Extended Durability – in what is called the synergistic effect between galvanized steel and paint, the zinc of the galvanized coating...
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Why paint over galvanizing may fail

Paint failure mechanisms are somewhat complex when paint is applied over hot-dip galvanized steel, otherwise known as a duplex system, and they may be manifested as peeling, flaking, or blisters.  And regardless of...
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Painting or powder coating system types to be used over hot-dip galvanized steel

While all recommendations for paint types over a properly prepared galvanized surface should be made by an industrial paint supplier, there are a few emerging patterns that may help in the decision making process. P...
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How does galvanized steel perform in seawater splash zones?

Splash zones are the most aggressive environment for hot-dip galvanized steel (or any other protective coating) because as the zinc coating reacts with the chlorides when wetted, zinc corrosion products are formed....
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Preparing the hot-dip galvanized steel surface for painting or powder coating

Similar to painting over black steel, surface preparation is critical when painting or powder coating over the zinc coating of hot-dip galvanized steel. However, before any surface preparation takes place,...
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What are the specific requirements for painting over galvanized steel?

The specifications for preparing hot-dip galvanized steel for painting or powder coating are ASTM D6386 and D7803, respectively. Successfully painting or powder coating hot-dip galvanized steel, also known as a dupl...
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