At least one of the thermally conductive ones are; not sure about the electrically conductive. Talk to them.
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Tempea, Ioan
Sent: Monday, February 26, 2018 10:47 AM
To: [log in to unmask]
Subject: Re: [TN] Conductive Epoxy Inspection Criteria on Flex for LED
Hi Dean,
Do you happen to know if Zymet epoxies are space qualified for outgassing and have you run qualifications with them?
I must confess I've never used Zymet and lot to lot consistency is something we don't exactly get with the epoxies we currently use.
Thanks,
Ioan
-----Message d'origine-----
De : TechNet [mailto:[log in to unmask]] De la part de Stadem, Richard D Envoyé : February 26, 2018 11:21 AM À : [log in to unmask] Objet : Re: [TN] Conductive Epoxy Inspection Criteria on Flex for LED
I can also speak for Zymet; I am currently using both its thermally conductive and electrically conductive epoxies at three different companies. Zymet makes an excellent product; it is extremely consistent from lot to lot. For automated dispensing, you need to understand the pot life, just as you would for any other dispensed epoxy, especially for SMT chipbonders. For extremely precise dispensing, the pot life may only be 10 hours before the changes in viscosity cause variations in the dispensed amount, but you can use up the rest of the tube after 10 hours and before its real pot life of 48 hours expires by dispensing manually, such as for touchup, etc.
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Wayne Showers
Sent: Monday, February 26, 2018 9:52 AM
To: [log in to unmask]
Subject: Re: [TN] Conductive Epoxy Inspection Criteria on Flex for LED
Although I am usually middle of the pack for efficacy of 3-D paste inspection, it is critical when applying conductive epoxies. The criteria that I am aware of or have utilized are as follows:
IPC-3406
IPC-3407
Before assessing visual criteria, I must first re-affirm Yuan-chia Joyce Koo's position that HALT is essential to process verification.
Normal prohibitions aside (do not use on a HAL (Hot-Air Lead-Free) or HASL (Hot-Air Solder (Tin-Lead) Level)), then the ideal is to make sure that the parts are not mashed into the epoxy. The best results I have achieved are with the epoxy compressed roughly 1/4 to 1/3, with 2/3 to 3/4 of the epoxy bond under the part terminations
Also, make sure your stencil house has epoxy experience as they will fabricate the stencil to different guidelines.
Also, two past resources for me were Zymet and Parker Chomerics. I have used conductive epoxies from both and they were helpful. Master bond also offers conductive epoxies but I cannot vouch for their tech support.
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