As I understand it, the phenomenon is electrochemical, and the conductive
path is not pure metal but ionic compounds. I wish I had a stronger
chemistry back ground. I have not heard of Pb or Nickel involvement but both
tin and copper. Never heard of nickel.
http://www.empf.org/empfasis/feb04/sirtesting.htm

> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of Vladimir Igoshev
> Sent: Tuesday, May 04, 2004 11:52 AM
> To: [log in to unmask]
> Subject: Re: [TN] Crystalline growth across a capacitor...the
> next stage
>
> I'm wondering whether all the dendrites are pure Sn? In my
> previous life I saw very similar problem with capacitors, but
> the dendrites were "made" of Pb and drew under a conformal coating.
>
> Vladimir
>
> Vladimir Igoshev, Ph. D.
> Senior Materials Researcher
> Research in Motion
> 451 Phillip St.
> Waterloo, ON, N2L 3X2
>
> Voice: (+1) 519-888-7465, ext. 5283
> Fax: (+1) 519-886-0863
> E-mail: [log in to unmask]
>
>
> -----Original Message-----
> From: Steve Gregory [mailto:[log in to unmask]]
> Sent: Tuesday, May 04, 2004 8:55 AM
> To: [log in to unmask]
> Subject: Re: [TN] Crystalline growth across a capacitor...the
> next stage
>
>
> Mornin' All!
>
> David Douthit sent me pictures to post that did jog my memory...go to:
>
> http://www.stevezeva.homestead.com
>
> and look at Capacitor Dendrites. Looks like conditions may be
> ripe in the previous pictures that I posted.
>
> -Steve Gregory-
>
>
> > Steve,
> >
> > Repost the attached jpg file showing the next stage after
> exposure to
> > moisture.
> >
> > You remember this one from last year!
> >
> > David A. Douthit
> > Manager
> > LoCan LLC
>

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