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Full Version: Why Can Aluminium Powder Coatings Fail?
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Polyester powder coating is should protect aluminium, providing a long-lasting, tough coating. But in certain circumstances, it may not last as long as it should.

Why should this be the case? The reasons are normally due to problems during the powder coating process.

If something goes wrong during the process, the aluminium surface can end up with various issues:

Filiform corrosion –  worm-like filaments appear under the powder coating finish, lifting it away from the metal, due to less effective pretreatment methods before applying the powder coating

Orange peel effect – the finished surface is not smooth due to a faulty application of the powder coat

Failure of the powder coating to stick to the surface – because of either the insufficient pre-treatment or faulty application of the powder coating layer.

Properly and carefully applying powder coating to aluminium surfaces should prevent corrosion.

But it’s also important to clean and maintain these surfaces once they have been coated. This is especially true in situations where they will face exposure to outdoor weather conditions. One example is powder-coated aluminium window frames.

There are remedial measures you should take if powder-coated aluminium surfaces become damaged and are therefore susceptible to corrosion.

One solution is to touch up any damaged areas with colour-matched liquid paint. This can work where there has been fading due to oxidation, or where there are scratches or blemishes.

Wear and tear can reduce the overall effectiveness of powder coating, so it’s important to keep on top of it.

Where there are more serious signs of corrosion, the best solution is to get the part or product re-coated.

But with a professional application of powder coating to aluminium surfaces in the first place, these types of issues are far less likely to come up.