Quote Originally Posted by BR549 View Post
What happens when you temper mild steel with salty water? Does it "become" AR500?
No. Different metals react differently do differ quench baths. Some metals become hard to the state of brittleness upon quenching and additional steps. You can soften hard steel by annealing it, you can't harden soft steel to hard steel standards. At least that what's I have been told and seen. Jim