I would heed the gold embrittlement caution.  You can have good 
solderability but that does not mean the solder joint will be reliable. I 
have witnessed boards that appear to have good solderability (maybe a 
little grainy) but if you flex or twisted the board you would hear 
cracking and some of the parts would actually fall off. 



Joel Alexander
Quality Assurance Manager
TT APSCO, INC. 




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03/15/2007 07:32 AM

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Re: [TN] IPC ENIG SPECIFICATION






Thanks for the prompt reply. I can do the gold calculations - lots of
stuff on the tech-net telling me how to do that. We have not seen any
solderability issues. I would still like an explanation of the reasoning
behind the minimum nickel thickness( besides a keypad type application).
Regards Steve Kelly>

Steve,
>
> I will likely solder quite well, but the gold is quite thick for
> soldering to without incurring the wrath of gold embrittlement.  I would
> not be so concerned about the thin nickel as the overabundance of gold.
>
> If the gold were nice and soft, it would be nice for gold ball bonding!
> But, the nickel is quite thin.
>
> If the numbers are correct, you did not receive ENIG - have them sent
> back
>
> Steve C
>
>
>


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