Electronics Forum | Fri Aug 22 09:07:22 EDT 2008 | blnorman
Sulfur is probably the culprit. Board supplier should be providing boards with anti-tarnish sheets between the individual boards. Also, cardboard is a major source of sulfur and so boards should not be shipped in cardboard.
Electronics Forum | Wed Aug 27 18:28:29 EDT 2008 | blnorman
We have an immersion silver board that has a brown discoloration after processing. It's not flux residue, that normally doesn't cause this condition. Elemental analysis shows less than 1% sulfur, and I thought silver sulfide is more a black color.
Electronics Forum | Mon Apr 26 14:40:07 EDT 2010 | blnorman
We had one product that used immersion silver plating. There were a couple of instances where we saw tarnishing, and elemental analysis confirmed the presence of sulfur. These boards did have the anti-tarnish sheets between boards, but somehow they
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