Im not able to tell if they have a use at all, crafted a couple of them but I dont know how to apply them. Sorry if this issue its a little silly but I couldnt find info about this anywhere else. Thanks

They're just a crafting item to create the actual upgrades. I mention them here:
https://github.com/thebrightspark/SparksHammers/wiki/Powered-Hammer

You should use something like JEI so you can see what they can be crafted into.

Thanks!!