did it missing a Ni plating?  http://www.johansondielectrics.com/ 
understanding-ceramic-capacitor-terminations
best of luck.
jk
On Sep 6, 2017, at 12:25 PM, Giamis, Andy wrote:

> Hi TechNetters,
>
> Here’s something I have not seen before.
> I have seven different ‘theories’ for what’s happening here.
> Three of which do not involve mythical creatures, illegal  
> substances or the alignment of celestial bodies.
>
> This capacitor is on a path that sees a lot of RF power.
> The unit went through 20 cycles of -70C to +115C while at nominal  
> power.  Temperature sensing suggests this device could be hitting  
> 170C.
> No, we normally don’t test to these extremes.
> The PCB has ENiG finish and the solder is SAC.   This is normal  
> SMT, no rework.
>
> I think I know in general what happened, but I am surprised.
> I don’t have an explanation for the formation of the big pocket on  
> the right.
> Has anyone ever come across any solder joints like this?
>
> Thanks Steve for uploading the pictures (links below).
>
> http://stevezeva.homestead.com/pockets_25.jpg
>
> http://stevezeva.homestead.com/Pockets_CS.jpg
>
> http://stevezeva.homestead.com/Pocket-left.jpg
>
> http://stevezeva.homestead.com/Pockets-right.jpg
>
>
> Best Regards,
> Andy
> Andrew C. Giamis
> Senior Failure Analysis Engineer
> CommScope
> 2601 Telecom Pkwy
> Richardson, TX, 75082, USA
>
>