Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Steam Aging of ENIG

gopinath A

#31734

Steam Aging of ENIG | 15 December, 2004

I heard that Steam Aging (storage) tests would be inappropriate for gold finishes. Is this a correct statement? If so, what are the reasons?

How bad is the shelf life of ENIG

This message was posted Add this forum to your site! Click to learn more. the Electronics Forum @

reply »

#31751

Steam Aging of ENIG | 15 December, 2004

We�d say that it�s incorrect that ENIG solderability protection cannot be steam aged. It�s true the immersion tin and silver cannot be steam aged.

We believe that most of the issues surrounding the poor performance of ENIG after steam aging is attributable to inadequate gold plating thickness. Thin gold plating allows corrosion of the nickel undercoat. Corroded nickel is very difficult to solder.

There�s a fair amount about this on the web, for instance: http://www.npl.co.uk/ei/presentations/storage.pdf

It�s possible that IPC-4552, Electroless Nickel/Immersion Gold (ENIG) Plating for Electronic Interconnections addresses your concerns.

On the shelf life concern, many have posted comparisons of various solderability protections on the web. Here's one example http://www.twi.co.uk/j32k/unprotected/pdfs/6feb03_aw6.pdf

reply »

SMT Custom Nozzles

 Reflow System