Aluminium parts are sometimes designed with non-aluminium inserts, such as rivets or threaded bushings. Any inserts of materials other than aluminium, titanium and some plastics will be destroyed by the pre-treatment or anodising solutions if immersed in our processing tanks. The ferocity of the reaction can severely damage the aluminium part in addition to destroying the insert and it can also damage our processing solutions.

Depending on the geometry of the part and the risks involved, it may be possible to mask off the insert using the same types of masking media used when areas are to be kept free from coating. This will add to the cost of the job and is not guaranteed to work as it is very difficult to completely prevent processing solution from reaching inserts, with disastrous consequences. The best solution (in terms of risk and processing cost) is usually to anodise aluminium parts and only introduce inserts of other materials after processing.

Some plastics (HDPE, Polypropylene, CPVC, PTFE) are safe to be in contact with our processing solutions. We can advise on the suitability of materials - please contact us.

Please always draw our attention to inserts of any material so that we can ensure parts are treated appropriately.


This page is provided for information only, it should not be considered advice and we cannot accept any responsibility or liability for your use of the information on this page. The information on this page is used and relied on at your own risk and you bear the sole responsibility for any outcomes. E&OE.