Electronics Forum | Sun May 30 18:52:35 EDT 1999 | Graham Naisbitt
| | | | | | I have always thought it to be a good practice to wash SMA's with water soluble paste (WS609) soon after reflow. Is there a time limit as to how long a board should sit after reflow before washing said board? For instance; processing a
Electronics Forum | Thu Sep 18 23:56:56 EDT 2008 | trynders
am having wetting issues with two Burr Brown Op amps. Both are SOICs with NiPdAu lead frame finishes. I have attached a photo that shows a black streak the length of the lead (before soldering). This appearance is consistent of all leads and is exist
Electronics Forum | Fri Mar 14 11:04:54 EDT 2008 | herman
Samir, To correct some misconceptions on the answers to your question, and "what you know from experience": With both ENIG (Electroless Nickel/Immersion Gold-IAu) and IAg (immersion silver), soldering does not take place to the gold or the silver. Wh
Electronics Forum | Mon Jan 31 12:24:24 EST 2000 | Dave F
Robert: Several points: 1 Dross is a mixture of various things with no "fixed" composition: � The obvious things are metal oxides mixed with metal and this can vary in color with temperature and composition - remember some intermetallic oxides form
Electronics Forum | Fri Mar 17 03:27:20 EST 2000 | Wolfgang Busko
Darren: Do you know what these residues are ? How clean is your solderbath ? How often during a day do you clean it ? My first impression is that you deal with oxides. M2C Wolfgang
Electronics Forum | Wed Dec 14 21:19:36 EST 2005 | davef
Heavens to Murgatroyd, we agree with Russ that "black pad" could be the cause of your solderability problem, but oxidized nickel is an additional explanation. While its often easy for assembler to jump this conclusion, it sounds like you've been bla
Electronics Forum | Thu Sep 05 23:32:29 EDT 2013 | winson16
This connector was designed with gold flash plating and the lead's surface was become dull and some black mark was observed on the contact surface.
Electronics Forum | Mon Nov 30 23:45:20 EST 1998 | Kallol Chakraborty
Hi folks , Lately we are seeing a lot of rawcards with black spots on the pads - most of them have Au finish(immersion gold) . We did a lot of inspecton after wave solder and found that only (fine pitch) QFP are affected the most. Our inspection /te
Electronics Forum | Tue Dec 05 16:08:41 EST 2006 | dphilbrick
I would suspect if you had a full evaluation done there would be the same issue with Nickel oxidation everywhere. The reason BGA's fall off (or have solder connection issues first) is due to their size. A slight flex in the board has a much larger im
Electronics Forum | Thu May 05 17:15:46 EDT 2005 | russ
You got what I think someone has called a "cold melt". If you were to run your removal profile awhile longer you would not see this. Anyway, you don't have any issues as this is very common (at least in my experience). FYI I was thinking your oxid
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