Hello Joe,
I am curious about the "evidence" that you are referring to, to the effect
that "lead-free" solder will make electronics less reliable.

Three questions:
1) which lead-free alloy(s) does this refer to?
2) which products have failed in the field and what was the failure  mode?
As you know, there has also been SnPb failures in the field (Werner  can tell
you more about that), and that did not make SnPb technology unreliable  as a
whole.
3) where has the evidence been published?

In the same vein, I am also wondering about the SWATCH report  that John
brought to the attention of this forum. John can probably enlighten us  on this.
The pictures I saw were very dark and not too clear (originals  are probably
sharper but I have not had the privilege of seeing them).   The text highlights
tensile forces as being the driver behind the  growth of tin whiskers.  All
technical studies I have seen to date suggest  that compressive (not tensile)
forces drive the growth of tin-whiskers. I am  curious as to why tensile forces
would prevail. Any physical evidence or  measurement that you, or others, can
share to that effect will be  appreciated.  Also, I was wondering if other
elements, other than  exclusively Pb, have the potential of preventing
tin-whiskering.  The  SWATCH report seems to focus exclusively on SnPb alternatives.

I apologize for my ignorance here and I am looking forward to learning more
from this forum about tensile forces driving tin-whiskering, as well as
"lead-free" being less reliable than good old SnPb. By the way, my questions are
purely technical, which I hope remains acceptable to the forum.

With best regards,
Jean-Paul


In a message dated 5/22/2006 1:11:11 A.M. Eastern Standard Time,
[log in to unmask] writes:

In sum  lead-free solder will not make the environment better, but  it  could
well make it worse. It will not use less energy, it will use   more. It will
not
be cheaper, it will be more expensive. It will not  make  electronics more
reliable, evidence is that it will make them  less so.





Quote of the month:

"Research is what I'm  doing when I don't know what I'm doing", Wernher von
Braun.
_______________________________________________
Jean-Paul  Clech

EPSI Inc., P.O. Box 1522, Montclair, NJ 07042, USA
tel.:+1  (973)746-3796, fax: +1 (973)655-0815

_http://www.jpclech.com_ (http://www.jpclech.com/)

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