Trouble bonding to electroless nickel plated aluminum

[tamon499]

I am experiencing an adhesive failure using a silver filled epoxy. The bond has an adhesive failure at the nickel plated surface. The aluminum part is plated with a med phosphourous nickel. The same epoxy bonded to stainless steel has twice the bond strength and cohesive failure. any suggestions?

 

[ScottyUK]

In hybrid chip & wire assembly we used a plasma cleaner immediately prior to die bond with a silver-loaded epoxy. Substrate was either Pd-Ag, gold, or a low-temperature glass, and the plasma cleaning was to remove any organics on the surface which could weaken the bond.


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If we learn from our mistakes I'm getting a great education!

 

[olmanpete]

Surface contamination is the root of most bonding problems as you probably know. I would get a SEM and a scan for surface elements. I would also try Boron Nickel. That sometimes bonds better.

 

[unclesyd]

You might want to consider a promoter/primer from Reltek for your application.

http://www.reltekllc.com/adhesives-coatings.html#P301