I’d say a two by four OR heavy stick +long string or 50 duct tape or welder charges + sharpened rebar. Maybe a chunk of steel for added weight so it’s more like a pick?
So it’s more like a axe handle, with the rebar secured at the end at a ‘T’ Might be a better method then trying to bend the rebar. It’d counter-balance it’s own weight, too.
Tools could be a tool of cutting of 1 or more to whittle the handle and form a slot for the rebar to be secured in.
Might work like a digging stick? I dont think you could mine or clear rubble, but it should smash doors and furniture things apart, since you could stick it in and really pry things apart. It should have a bonus against armor, maybe a to-hit penalty.