Annealing – Generally furnished annealed. Raise to 1,550°F slowly, not to exceed 400°F/hour. Hold at temperature one hour per inch of greatest cross section (2 hour min.) Cool slowly in furnace. Do not exceed a cooling rate of 50°F/hour to 1,000°F. Cool to room temperature in furnace or air; 235 BHN max.
Forging – Pre-heat at 1250°F, then to 2000°F stop at 1700°F, cool slowly.
Hardening – 1,725°F/1,775°F, air quench to 150°F.
Preheating – 1,150°F /1,250°F, raise to temperature slowly, not to exceed 400°F/hour, then to 1300°F/ 1,400°F.
@ 350°F typical hardness Rockwell “C” 62.
@ 950°F typical hardness Rockwell “C” 48.
(Minimum time at tempering temperature is one hour per inch of thickness, even on thin sections. 2 hour minimum. Heavier sections should be held a temperature sufficient for uniformity of temperature.)
* Above values are typical and are not guaranteed.