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Reply To: | TechNet E-Mail Forum. |
Date: | Mon, 20 Jul 1998 11:45:30 -0700 |
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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.
>
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