Powder coating sprays a dry, electrostatically charged polymer onto a grounded part, then cures it in an oven where it flows into a continuous film. Done right it is tougher and more even than wet paint and produces almost no solvent waste. On aluminum, though, the result lives or dies on the step most shops rush — pretreatment.
The process, in order
- Clean & etch — degrease and lightly etch to remove oils and the native oxide layer.
- Conversion coat — chromate or chrome-free pretreatment gives the powder a surface it can chemically grip.
- Apply — electrostatic spray wraps the charged powder evenly around edges and recesses.
- Cure — typically 180–200°C for 10–15 minutes so the film cross-links fully.
Specifications
| Parameter | Detail |
|---|---|
| Substrate | Aluminum sheet, extrusion, castings and welded assemblies |
| Film thickness | 60 – 120 µm typical |
| Gloss levels | Matte · satin · gloss · textured · metallic |
| Color matching | RAL / Pantone / sample-matched |
| Pretreatment | Chromate or chrome-free conversion coating |
| Max part size | Confirm per batch — line and oven dependent |
Where it goes wrong
The two failures we see on parts coated elsewhere are flaking and uneven color. Flaking is almost always skipped or weak pretreatment — the powder never bonded to the metal. Uneven color usually means inconsistent film thickness or an under-cured oven cycle. Both are process-control problems, not powder problems, which is why we keep coating in-house rather than subcontracting it.
Pairs with
We coat parts we laser cut and bend in the same facility, so a finished bracket or enclosure ships ready to install.