Conversion Coating – Alocrom/Alodine

Alocrom (or Alodine in the US) is a Chromate conversion coating that is applied to aluminium alloys, which provides a level of corrosion protection. Alocrom is also good for paint adhesion and is electrically conductive. Poeton can apply the process to the MIL-DTL-5541 approval.

Alocrom can be applied by either dipping or brushing. It’s a relatively quick and simple application process compared with other surface treatments. The treatment yields a very characteristic yellow colour.

It should be noted that Alocrom is a hexavalent chrome process that is under threat from the REACH regulations and a usage sunset date just a few years away. Poeton has therefore invested a huge amount of R&D resource over the last 7 years evaluating and perfecting the application methods of the Alocrom alternatives, such as: Surtec 650, Iridite NCP, Socomore TCS PACS and Lanthane. Please contact us for more details on the current alternatives.

Materials Processed:

Aluminium Alloys

Tank sizes: Gloucester

1.5m x 1m x 1m

Tank sizes: Cardiff

1m x 1m x 1m

Tank sizes: Poland

0.8m x 0.8m x 0.9m

The tank sizes shown above are approximate sizes only. If you have a larger part then please contact us as we may still be able to help.


Electrical icon

Electrically conductive

Corrosion icon - acid spilling on to rectangle

Corrosion protection

Blue rectangle showing growth on top

Thin film, no dimensional change

Blue paint brush icon

Good paint adhesion

Blue rectangle line icon with cross lines showing good structure

Good integrity, can protect even when the component is lightly damaged.

Square icon with cracks replicating fatigue

Minimises the fatigue loss, compared with anodising techniques.


Conductive spot faces

Fine tolerance machined parts

Aerospace painted components