dbrandler,
        Tin whiskers occurs with pure elements only.  Immersion tin uses
very small amounts of bismuth to "contaminate" pure tin.  The now impure tin
will not form whiskers. The impure tin is further contaminated by the
addition of lead upon soldering.  (I have seen a reference that SnPb will
form whiskers, but I don't believe it).

Ryan G.

> -----Original Message-----
> From: dbrandler [SMTP:[log in to unmask]]
> Sent: Thursday, February 10, 2000 1:18 PM
> To:   [log in to unmask]
> Subject:      Re: [TN] White Tin PWB
>
> Hello,
> I'm curious. What happened to the tin whisker problem? Dan Brandler.
>
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