Electronics Forum | Thu Apr 15 08:23:47 EDT 2004 | prod
hi, Having put a copper socket trough a wave soldering machine, and then through a DI wash, the boards have been dried and after a few days a green residue has been noticed on the copper. any suggestions? not drying properly maybe? or could it be th
Electronics Forum | Thu Apr 15 11:15:30 EDT 2004 | patrickbruneel
Pure (red) copper oxide is green, its not a residue its just oxidation. In your case water and heat will accelerate the oxidation process of unplated or unprotected pure copper. The best way to avoid this from happening is use a socket with tin or n
Electronics Forum | Fri Apr 16 11:03:35 EDT 2004 | davef
Your copper corrosion is not good. It indicates that you have not done a good job in cleaning. [We assume this is a medium green color, not unlike the color of the solder mask on your board, that is almost like a translucent lacquer; rather than th
Electronics Forum | Fri Nov 03 11:30:29 EDT 2017 | davef
regarding dwl comment, "For low volume hand assembly, deionized water or IPA should work fine." Deionized water: Deionized water is corrosive. It needs to be removed. Proof? Drop a copper coin into a covered jar of DI water and watch what happens ov
Electronics Forum | Thu Jan 29 09:18:36 EST 2015 | davef
Nichrome, manganin, phosphor bronze etc are easy to solder ... the hard part is removing the corrosion * Manganin: 86% copper, 12% manganese, 2% nickel. Often, it's used in making cryogenic measurements, due to its low heat loss. * Select a flux for
Electronics Forum | Thu May 11 11:25:56 EDT 2017 | davef
Key to Rosin Fluxes [from SUPERIOR FLUX & MFG. CO.] Type R (Rosin): Non-activated rosin flux for soldering copper. Residues are non-corrosive and non-conductive. Type RMA (Rosin Mildly Activated): Mildly activated rosin flux that contains no chlori
Electronics Forum | Sat May 09 23:05:17 EDT 2009 | kareal
Davef, It seems the tin resist residue on copper trace is root cause of whitish layer. but it could explian why I could not detect tin on fresh unit without UHAST. I have performed X-section and EDS analysis on many fresh units,but no any tin was
Electronics Forum | Thu Dec 08 08:13:48 EST 2005 | grantp
Hi, Copper oxide is green right? So the green residue after a few days is corrosion of the wire? Regards, Grant
Electronics Forum | Fri Jul 07 09:15:23 EDT 2000 | K. Chak
Hi Dave, This particular p/n calls for print&etch for wet process..and the problem occured due to surface contamin. with resist residue resisting copper from etching off. The high pressure nozzle was a problem at developing oper. and it is fixed now
Electronics Forum | Wed Jul 17 03:36:00 EDT 2002 | robbied
Answers are: *Mainly copper and potassium. *it looks like a soft growth. *customer will not accept this, hence the returns. These boards are either reworked or scrapped. *Flux is not an issue. *The cleaning process has been found to be the cause of t
