You don't use "solders" for "welding".
You can take solders and "weld" them together by fusion and mixing in
the molten zone of both metals.
Would you settle for "braze" as a fastening method?
Do you mean solder or weld?
Or is it immaterial and you just want to stick these two metals together
with something metallic using heat, not some adhesive?
Yes, it sounds like nit-picking except there are fairly well accepted
definitions of "weld" and "braze" and "solder" as joining processes.
Indium Corporation (the name may have changed) was always one of my
favorite aerospace sources on low temperature metal joining methods.
So, at least you have a reference to a supplier of joining materials for
the aerospace inductry.
I might call on Electrofusion.... who has evidently been bought up by
someone. They are right outside Stanford California. The firm
specialized in difficult fusion joining techniques - and machining
beryllium brazing beryllium into complex lightweight structures.
Each of the above will be happy to give you some more names if you call
them, and maybe even if you email them, but it is less likely because
email is so impersonal and low cost.
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