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Chromate conversion coating time limit prior to wet painting

Is there a time limit to the effectiveness of chromate conversion coatings on aluminium prior to wet paint processing? I will be buying a machined aluminium forging from a company in Europe. The part will be chromate conversion coated prior to shipment to the US. This transportation by boat will take approximately 6-8 weeks. Upon arrival in the US the part will be processed through a wet painting process. The question I have is does aging of the chromate conversion coating degrade it's performance and will it affect the paint application? Paint adhesion is one concern in particular.

Mark Lindorff
Aerospace - Tucson, Arizona, US
2004

Chromate conversion coating is actually a very good paint base. If the surface is not scratched during shipment or otherwise compromised there is no reason for you to worry about any problem with paint. Normally after chromating parts should be cured at room temperature (60-100 °F ) for at least 24 hours.

Mussadiq Hussain
- Canyon Country, California, USA
2004

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Let us assume that the European applicator let the part "cure" for 24 hours at room temperature, and then wrapped it in non-sulfur bearing paper and that the part did not get scratched during handling and that the part was not touched by bare human fingers - then you may paint with confidence.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

2004