O1 Tool Steel

Chemical Analysis:
Carbon .85/1.00
Manganese 1.40/1.80
Phosphorus .030 Max.
Sulfur .030 Max.
Silicon .50 Max.
Chromium .40/.60
Vanadium .030 Max.
Tungsten .40/.60
Molybdenum -------
Cobalt -------
Tempering Temp. º(F): Hardness Rc
As-quenched 65.0
300 63.0
350 62.5
400 62.0
500 60.0
600 57.0
700 53.0
800 50.0
900 47.0
1000 44.0
1100 39.0
1200 31.0

Uses:

Punches, dies, trim dies, blanking dies, forming dies, stamping dies, label dies.

Forging/Rolling:

Preheat to 1200° F and hold for uniformity.  Then raise to 1850° F - 1950° F.  Do not forge or roll below 1500° F, cool slowly from the forging or rolling temperature.  Do not normalize.

Annealing:

Heat slowly to 1450° F and soak thoroughly.  Furnace cool slowly at a rate of 20° F per hour to 900° F, remove and air cool.  Expected Brinell hardness 202 max.

Hardening:

Heat to 1475° F and hold 1/2 hour per inch of greatest thickness.  Large parts should be preheated at 1200° F and held for uniformity before raising to the hardening temperature. Oil quench 150° F and temper without delay.

Tempering:

Temper before the parts have cooled to below 150° F.  Small parts should be held a minimum of 1 hour per inch of greatest thickness and large parts 2 hours per inch of greatest thickness.  A single temper is sufficient, but double tempering is a good insurance policy.  For most applications a tempering temperature of from 350° F - 450° F is usually specified for the O-1 analysis.  The above tempering table may be used as a guide.  However, since 1/2" dia. specimens were used for this test, it may be found that heavier sections are several points lower.