James,

How about acrylic conformal coating?
You are so far above the Tg of acrylics that the coating can "flow", melt, evaporate, or all the above!

(Not to mention letting contaminants reach the surface!)

David A. Douthit
Manager
LoCan LLC


"Marsico, James" wrote:

> Hello Technet:
>
> I think I may have asked this question a while ago (or something similar)
> but couldn't find anything in the archives.  I have a surface mount assembly
> that gets installed into a top assembly housing, with covers.  The test guys
> want to subject this assembly to 125 degrees C for 112 hours.  Assuming that
> all of the components are rated for this temperature, is there anything else
> that says this isn't a good idea?  I'm thinking about the solder joints,
> maybe decreased reliability due to excessive grain growth?  How about
> acrylic conformal coating?  The PWB is polyimide, so this shouldn't be an
> issue.  Anything else?
>
> Thanks again...
>
> Jim Marsico
> Senior Engineer
> Production Engineering
> EDO Electronics Systems Group
> [log in to unmask] <mailto:[log in to unmask]>
> 631-595-5879
>
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