Folding copper?

[u/Swimming_Guarantee29]

I would like to make a higonokami inspired balisong. What does it take to forge a 3mm plate of copper around 3mm of steel as a handle piece?

I have a few ideas, but if there is a potential for cracking or tearing of the copper then I would like to be prepared in advance to alleviate these stresses.

I would like to do a nice work hardened, hammered finish ideally, so the 3mm thickness is with this in mind.