Here's a good link that illustrates the issue:
 
http://www.aciusa.org/leadfree/LFS_SUMMIT-PDF/07_SAMPSON_NASA_Lead_Free_
Inputs.pdf

Another good link that will give you hours of browsing the whole whisker
issue:

http://nepp.nasa.gov/WHISKER/photos/index.html

Kind regards,

-Steve Gregory-
Senior Production Engineer
OAI Electronics
6960 East 12th Street
Tulsa, Oklahoma 74112

(918) 836-0507
(918) 706-2779 CELL
(918) 836-0184 FAX 

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Kane, Amol (349)
Sent: Thursday, April 13, 2006 6:51 AM
To: [log in to unmask]
Subject: Re: [TN] Tin whiskers and conformal coating

There have been studies done regarding this issue. They seem to be of
the opinion that since the whisker tip area is very small, the pressure
at the surface of the tip is large, and hence it can easily pierce the
1-3 mil thickness coating layer. Conformal coating is still mentioned as
one of the forms of preventing the tin whiskers from touching each other
and shorting (but not as a technique to inherently prevent the formation
of Sn whiskers). The ultimate decision will have to consist of testing
the efficacy of the type of coating for a particular application.

Amol Kane
M.S (Industrial Eng.)
Process Engineer
Harvard Custom Manufacturing
941 Route 38  Owego, NY 13827
Phone: (607) 687-7669 x349
[log in to unmask]

 -----Original Message-----
From:   TechNet [mailto:[log in to unmask]]  On Behalf Of David Hudson
Sent:   Thursday, April 13, 2006 6:33 AM
To:     [log in to unmask]
Subject:        [TN] Tin whiskers and conformal coating

Is there any experience or thoughts about whether the application of
conformal coating would help with the prevention of tin whiskers?

Thanks,
Dave
--
++++++++++++++++++++
David Hudson

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