Boron case hardening process?

[coppercone2]

I have boron metal solution in hydrocarbon oil. As an experiment i thought i can case harden something by wrapping something that has been smeared in the oil in copper sheet and then heating it to red hot with a propane flame (for say 1 hour).

Is this at all likely to work? Do you absolutely need boron carbide or will elemental boron work?