I have seen such problem on SMD component with silver-palladium terminal.
These were first intended to be used in hybrid  and assembled by conductive
glue, however we ended up using with reflow soldering and we had occurences
of "broken" terminal connection (the contact was not there anymore and the
part would eventually come loose (without its terminals).  The cause is
that the silver-palladium leach into the solder paste during the reflow
process at high temperature. The cure was to switch to tinned terminals.
If you really need to use these parts them you should try to use solder
with a small amount of silver wich will somewhat prevent leaching.

Jean-Luc Lehmann




                    "Marsico, James"
                    <James.Marsico@D        To:     [log in to unmask]
                    P.AIL.COM>              cc:
                    Sent by: TechNet        Subject:     [TN] Soldering to palladium silver
                    <[log in to unmask]
                    >


                    13.08.01 12:56
                    Please respond
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                    E-Mail Forum.";
                    Please respond
                    to "Marsico,
                    James"





Has anyone come across any process or reliability issues when soldering
chip
capacitors with a palladium silver finish without pretinning first?  We
have
a customer who put us on stop work because they have an issue with this.
Any info will be appreciated.

Thanks in advance,

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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