Hi Paul M,
I think that what Paul K tries to say is " please wait, I'm thinking ".
Paul Klasek is next Nobel prize literature winner, oh, you already knew that!
Concerning 'flexible' conductive epoxies, I'm personally a bit confused. You have to specify what you mean with flexible. Everything is flexible. Even a diamond. Cullinan II is not perfectly matched to Betty's crown, both move, but as long she does not have this hat on when snowscootering in Arctic, or canoeing on Yan-Tze-Kian I think the mismatch is tolerable.
Talking about electronics, there are many sorts of joints where adhesives are used, and many requirements to fulfill. The dream is to get a joint that is electrically like Copper, mechanically like chewing gum, environmentally like glass, and thermally like Diamond. And costs little! And an abundancy of suppliers! And be repairable! Does not exist. Will never exist. Mother Nature stopped that billions of years ago. (If you talk with an adhesive salesman, you will get a more positive response.)
I stumbled into a problem years ago, that called for a 'flexible' solder. I had to solder mount a ceramic microwave window onto an aluminium structure, TCE mismatch factor 3! We built a FE model and let ANSYS do the job. She told us to make an extremly high, and extremly well controlled solder joint, free from pores, with well defined meniscus around the periphery. So we dead what miss Ansys said, and got a solder joint that was capable of 500 tempcycles instead of 1 or 2. It worked. But we did not use a 'flexible' solder, we used an ordinary solder and made best of it contra the environmental conditions.
Back to your 'flexible' adhesive. Of course there are flexible adhesives, like silicon products with less than shore25. And Butylene that is exaxly like chewing gum. But, you are talking about a CONDUCTIVE adhesive. Now the scenario is immediately narrowed to a few products, because conductivity and elasticity are not great friends. All 'electrical glues' are based on built-in metal particles, formed like sferes or flakes. These metalic particles hook against each other and form chains, electrical resistance much depending on the fragile contacts against each other. The best condition for making a stable and low resistance over the whole temperature range is a massive and stable polymer for keeping the flakes together. As soon as the polymer starts moving (expanding/contracting), many metalic flakes will loose contact with the nabor, and you get an increased resistance. Of course, the probability of contacting will never disappear, even if you pull the joint, or twist or misha!
!
ndle it, there will always be traces of electrical conduction on inside, but not a stable 10 milli Ohm which I presume is what you want. (If you just want current flow like ESD discharging, I guess any slightly carbonized adhesive will do).
So, there we are. 'For what purpose?' is the first question all adhesive involved will ask. Tell them about your resistance requirements over the temperature range. Tell them about your migration requirements. About your hardness requirements. About life expectancy. About both contrahents to be joined. And a number of more questions. I'll give you the mail adress to one of the many suppliers which can send you a ready-to-fill-in list, and consequently you will get a proposal or two.
Did I let you down? No? Good. And forgive Aussilek. He is a member of MENSA, and these guys with an IQ>150 are not easy to understand. I have never understood one word from him, don't tell him, please.
Mail to wonderful Julie, she will give you the customer task list I mentioned. Her adress is : [log in to unmask]
Best regards
Ingemar Hernefjord
Ericsson Micorwave Systems
PS. If you need more expert help, I have a whole list of such crazy horses.
------------------------------------------------------------------------------------
-----Original Message-----
From: Paul Maciejewski
[mailto:[log in to unmask]]
Sent: den 13 januari 2000 13:10
To: [log in to unmask]
Subject: Re: [TN] Please translate !!!
Can any one tell what this guy is talking about?
---------------------- Forwarded by Paul Maciejewski/ElecTec/Teledyne on
01/13/2000 07:13 AM ---------------------------
Paul Klasek <[log in to unmask]> on 01/12/2000 04:53:43 PM
To: "'TechNet E-Mail Forum.'" <[log in to unmask]>, Paul
Maciejewski/ElecTec/Teledyne@Teledyne
cc:
Subject: RE: [TN] Flexable conductive epoxy
Geee, Thanks Paul (what ever happened to Steves Club); I just hate riot spot
lights.
I just took my polymer file home (been indicated by boss that my foot high
invisible desk is mildly contravening Co's clinical image) , soo all my
grace, ablestick (a very good Paul there in apply lab), dexter, loctite,
ciba, etc. contacts pile now in my home office.
Give me up to weekend (only time to breathe), meanwhile go through my howls
in IPC archives (we rechewed the contacts few times.
Webs of above may lead you somewhere (not saying where) ; Inge may break the
hibernation ;
and almost silent goldens may utter few words .
What is flexible ? Something you should do with conductive inks ?
Sorry to be sus, but I just hate to see an axe used as hammer by friends
(epoxies being generically flexible enough within their domain).
DETAILS please (on or off line if yo shy), vacuum pump you have I suppose.
cusn pk
PS
Just pondered, Paul, is there an open season on all of those WHY2K (!?!)
false prophets across the puddle ?
-----Original Message-----
From: Paul Maciejewski
[mailto:[log in to unmask]]
Sent: Thursday, 13 January 2000 6:34
To: [log in to unmask]
Subject: [TN] Flexable conductive epoxy
Hellooooooooooo! Techneters,
I'm looking for a flexible conductive epoxy that will meet NASAs space
requirements (little or no out gassing)
Do you have any suggestions??
Any leads would be appreciated, Thanks, Paul
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