restoring a hand trowel

hey there, I have a little hand trowel that im making a new handle for and restoring the steel, it was bent and rusted, I have acid bathed it to remove the rust, sanded it back, cut it shorter and rounded the tip to cut away the thin brittle rust eaten edge. now im just wondering if i can heat treat it to make the steel a little stronger, a little more resistant to bending, any tips?
I thought I would do some kind of annealing, tempering, quenching process using a blowtorch or an oven, and some oil.