Here is a garden trowel I made from a sheet of steel panel that came from an electrical pedestal.

I used a paper card cutout to help me figure out how it should be folded and then I traced it out onto the sheet and cut it out with a chisel.

It was quite a tedious project, lots of reheating and lots of careful hammering so that the handle didn't collapse on itself from too hard a blow.
Since the sheet metal is mild steel it cannot be hardened by quenching in water or oil, but it can be work hardened by hammering it.

The edges of the shovel blade are drawn out with sharp blows with a light hammer. This work hardens the metal and makes it much more rigid, the whole entire shovel is very hard to bend now. This sturdiness was easily obtained and now allows it to be used for leverage with out risk of it just bending.