Edwin, I don't have an answer to your question, but I have an aside you may find interesting. We have repeatedly found that exposure of electroless nickel to RMA flux and solder (wave), followed by an Axarel clean, turns the nickel a rather attractive black-navy color. The coloration cannot be removed with anything less than grinding off the surface, and no contamination can be detected on the Ni surface. Apparently the Ni is receiving a surface etch which changes the surface spectral response, giving a dark coloration. Just something to keep in mind . Ralph Vaughan Boeing-Atlanta > ---------- > From: Louis, Edwin[SMTP:[log in to unmask]] > Reply To: TechNet E-Mail Forum.;Louis, Edwin > Sent: Monday, July 20, 1998 1:17 AM > To: [log in to unmask] > Subject: [TN] Analysis > > Below is a question about solderability of electroless nickel. > > > ______________________________ Forward Header > __________________________________ > Subject: Analysis > Author: Edwin Louis at cmd-cs4-cc-p > Date: 7/10/98 3:52 AM > > > Dan, here is the message I was trying to send to Peter. > > > ______________________________ Forward Header > __________________________________ > Subject: Analysis > Author: Edwin Louis at cmd-cs4-cc-p > Date: 7/10/98 3:03 AM > > > Peter we have some electroless nickel on aluminum in which some > times > you can solder to it with Sn63 and RMA flux and other times you > cannot. Some people have suggested that there are various plating > types per various specs. that incorporate higher or lower amounts > of > phosphorus. The high phosphorus containing plating presumedly do > not > solder as well as the lower content plating. Another difference I > understand is that sometimes there are impurities of organics that > interfere with the soldering or perhaps heavy metal impurities that > > interfere with solderability. We would like to analyze and compare > the > two types of plating for these impurities. What do you suggest and > for > how many dollars? > It appears after conversation with Dan Sostak that perhaps Auger > would be best because phosphorus probably migrates to the surface > as > do organics. Because of the surface soldering process the culprits > are > probably on the surface. As far as trace included organics are co > ncerned, will microscopic FTIR fit the bill? I would appreciate > some > guidance from you on this matter. > > ################################################################ > TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c > ################################################################ > To subscribe/unsubscribe, send a message to [log in to unmask] with > following text in the body: > To subscribe: SUBSCRIBE TechNet <your full name> > To unsubscribe: SIGNOFF TechNet > ################################################################ > Please visit IPC's web site (http://www.ipc.org) "On-Line Services" > section for additional information. > For technical support contact Hugo Scaramuzza at [log in to unmask] or > 847-509-9700 ext.312 > ################################################################ > ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################