O1 COLD WORK TOOL STEEL

 

STRESS RELIEVING

Heat to 650°C /700ºC .  Hold for 2-4 hours and furnace cool.

 

HARDENING

Before heat treatment, sufficient machining should be carried out to remove
surface decarburisation.
Preheat thoroughly to 650°C / 700°C and then raise more rapidly to 780°C / 790°C
in a controlled atmosphere furnace or, preferably, a neutral salt bath.  Quench in oil.
A useful alternative is box hardening using spent charcoal placed away from the
working faces.  Larger sections may be hardened from 810°C / 820°C.