Hello Lee,

In a message dated 5/17/2004 6:16:38 PM Eastern Standard Time,
[log in to unmask] writes:
However, test vehicles, and their respective test plans
(thermal cycling, mechanical shock, etc.) and simulations, may not
completely or accurately represent the "real world".

That is correct, however it is the nature of reliability engineering that,
with any new product or re-design, accelerated testing and modeling are about
the only tools available to make educated guesses and help building in
reliability.  The specific tools should be evaluated critically for their own
limitations.  Field experience, which takes time, will then confirm whether the
predictions were right or how much of a safety margin was achieved.
As somebody mentionned earlier, the above reliability type of work is called
"doing one's homework".  I call it a worthwhile investment.
Has anyone built deliverable Lead Free hardware and is willing to share
their field data?
Unfortunately, the hard field data is not widely published, especially when
failures have occured.  I had mentionned a couple of lead-free field failures a
couple of weeks ago but I can't give specifics other than the applications
were under harsh-environment (automotive).
Besides that, I have not heard of catastrophes although the accumulated field
experience is still limited, in general  (compared to 50+ years of SnPb
usage). Time will tell how much of a reliability margin we can expect.

With best regards,
Jean-Paul






_______________________________________
J-P. Clech
EPSI Inc.
P. O. Box 1522, Montclair, NJ 07042, USA
tel.: +1 (973)746-3796; fax: +1 (973)655-0815
Web: http://jpclech.com

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