I don't know exactly where you have this condition occurring, but if 
     it is around hardware it could be oil residue.  Sometimes hardware is 
     coated with a thin coat to help prevent corrosion on them.  We have 
     noted it most on metallic screws, bolts, nuts and washers.  Sometimes 
     this coat of oil is difficult to remove depending upon what cleaning 
     method is used.  Hope this helps.
     
     
     Dwight Nolen
     MFG Quality Engineer/QA Supervisor
     Frontier Engineering
     Stillwater, Oklahoma
     405-624-5329


______________________________ Reply Separator _________________________________
Subject: Assy: green stuff
Author:  MIME7:[log in to unmask] at INTERNET
Date:    3/25/97 5:50 PM


     
Hello,
     
At the burn in operation, we sometimes find a green stuff as well as black 
stuff that look like corrosion and they're located under the conformal 
coating. When analysing the stuff, it came out as copper chloride for the 
green spots and copper sulfide for the black spots.  Any idea as to where 
they could originate from ?
     
Thank you.
     
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