Copper foil to fiberglass or carbon fiber bonding 3

[flyerfly]

I am looking for recommendations on bonding copper foil into a fiberglass or carbon fiber laminate. The copper foil will be near the surface of the laminate but will not be exposed to corrosion environments.

I am having a hard time getting a good bond. Would the use of BR127 or BR6747 help me alot? I do not want to grit blast the copper foil if possible. I do want a pretty good bond though because of the CTE mismatch and a service temp going from -40 F up to 160 F.

Suggestions are greatly appreciated.

 

[cloa]

Why is it wanted to join the copper foil to the laminate?

 

[Demon3]

I'm getting plenty of hits for "copper tape"

e.g.

http://www.shieldingsystems.eu/index.php?p=Nieuws&id=94&Lang=2

Chris DeArmitt

"Knowledge has no value except that which can be gained from its application toward some worthwhile end."
Think and Grow Rich - Napoleon Hill

 

[MikeHalloran]

Perforate the foil, or use screen or knitted copper cloth.



Mike Halloran
Pembroke Pines, FL, USA

 

[berkshire]

flyerfly
I think you had better explain what you want the foil to do. Are you looking for lightning strike protection, or static charge dissipation such as on a fuel tank, or for a radio antenna?
Static charge dissipation on a fuel tank can use Adhesive backed foil tape, so can a radio ground plane or antenna.
Lightning strike protection is another animal completely, and as Mike halloran says you would need a screen or Knitted material.
B.E.

 

[flyerfly]

I appreciate those that want to help on this issue. I am aware of the different uses and why not to use one or the other (foil vs mesh). Suffice it to say, in my case I need to use foil. My primary question is bonding, not why I chose a particular material. This application is not lightning protection it is EMI/RF related. I am already familiar with the tape and it is not applicable in this case. I just want to know about bonding promotion. Thanks.

 

[berkshire]

If that is the case an acid etch of the foil in the manner used for printed circuit boards is in order.
B.E.

 

[Compositepro]

Yes, clean and etch the foil. Primer will not improve adhesion but will improve corrosion resistance and can be used to protect treated metal surfaces for later bonding.

 

[rajasai]

I would try getting a good surface prep on the foil, maybe use a scotch bright pad. Remember to move in a horizontal and vertical pattern and not in circles. Then clean with acetone.

I would also do a water break test to see if I have a good surface prep for bonding. Have you tried using a polyester adhesive film for bonding? Finally I would vacuum bag the laminate for good compaction and throw it in an oven for curing. If possible perforating the foil would be a good idea as well.

Below is a random website I found for adhesive films. I hope this helped.

http://www.adhesivefilms.com/polyester_PAF.htm

 

[spudpeeler]

ASTM D2651 provides steps for preparing a surface for bonding. In the case of copper the recommended procedure is:

1) Degrease

2) Immerse for 1-2 minutes at 77F (25C) in a solution of
42% Aqueous FeCl2 soln. - 15 pbw
Conc. HNO3 (s.g. 1.41) - 30 pbw
DI water - 197 pbw

3) Rinse in cold running DI water.

4) Dry immediately with clean pressurized air at 77F

 

[MikeHalloran]

Getting a bond to the laminate is the easier problem.

For EMI/RFI protection, you also need to terminate the edges of the foil, continuously or pretty close to it, to adjacent metal structure/ surfaces. That's where the foil tactic, er, falls apart, especially if the joint has to be separable.

I don't have any good solutions for that problem, but I've seen quite a few tactics that didn't work.




Mike Halloran
Pembroke Pines, FL, USA

 

[06057]

What type of fiberglass are you using? There is usually sizing on the fibers which will prevent getting a bond with adhesives. I suggest using a PSA and laminate to the foil then strip the liner and laminate to the fiberglass.

Scott