How to hardened steel?

Question

hardening os steel

example of hardened steel

Answer 1

get it red hot and quench it in oil a few times

Answer 2

Get it red hot or as hot as you can and the put it in cold water. Do this repeatedly. The molecular structure strenches and then stays the more you stretch it the more durable it becomes.

EXP-cast iron ( I think)

Answer 3

Try this

http://www.key-to-steel.com/Articles/Art...

Answer 4

The hardness of steel is determined by its molecular and microscopic structure.  Hardness can be changed by thermal treatment (heat treating/tempering), chemical treatment (such as case hardening), and physical working (cold working/cold rolling).