That's an awful high initial resistance. We would not accept that. As
for the second part of the question, I have several logical theories,
but would need to know more about the materials, tests and mechanical
juxtapositions.
Dewey

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Eric CHRISTISON
Sent: Thursday, July 16, 2009 1:14 AM
To: [log in to unmask]
Subject: [TN] Silver epoxy - related question

Interesting thread which prompts me to raise a related question.

I'm using silver epoxy as part of an EMC/ESD shield. It connects a 
conductive enclosure to a PWB ground plane.

Generally we get a DC resistance across the epoxy joint of about 3 Ohms.

However after we subject a device to an ESD spike we find the resistance

drops by maybe an Ohm or so.

Anyone got an idea what's happening?

Thanks,



John Burke wrote:
> Thanks to all for the replies on silver epoxy - they are as always
much
> appreciated.
>
> Best regards
>
> John Burke
> (408) 515 4992
>
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-- 
Eric Christison Msc
Mechanical Engineer
Consumer & Micro group
Imaging Division

STMicroelectronics (R&D) Ltd
33 Pinkhill
Edinburgh EH12 7BF
United Kingdom

Tel:	+44 (0)131 336 6165
Fax:	+ 44 (0)131 336 6001

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