O1 Product Guide

Applications | Specifications | Mechanical and Chemical Data | Tolerances

Overview

Oil-hardening, general purpose tool steel that holds its size and shape with excellent accuracy when being heat treated. While not as strong or wear resistant as A-2 or D-2, it experiences significantly less distortion during the heat treating process. Typically used in rolls, punches, shear knives, food processing knives, and gauges.

Common Trade Names

UNS T31501, AISI Type O1, Presco, Oilcrat

Other Resources

Weight Calculator | Mill Test Reports

Products

O1 Drill Rod | O1 Rectangle Bar | O1 Square Bar

Specifications

ASTM	SAE
A681	J437

Applications

Blades
Gauges
Tooling

Hardness	Heat Treat Temp.	Quench Medium	Applications	Disadvantages
O-1 Tool Steel Heat Treatment
As Shipped: Rockwell 88-95B After Heat Treating: Rockwell 62-64C	1450°-1600°F	Oil	Taps, Reamers, Knurling Tools, Shear Blades, Drills, Coining Dies, Trimming Dies	Oil hardening tool steels tend to experience less distortion during the quench operation, but they do still show distortion from the original size. The hardening operation is more thorough than with water hardening steels, but not as thorough as the air-hardening grades.

	Annealed	Hardened
Physical Properties O1
Density	0.283 lb/in3	0.283 lb/in3
Ultimate Tensile Strength	104.5 ksi	300 ksi
Yield Tensile Strength	58 ksi	N/A
Shear Modulus	11,200 ksi	11,200 ksi
Shear Strength	58 ksi	N/A
Fatigue Strength	40 ksi	N/A
Hardness Rockwell \| Brinell	B88-95 \| 177-212	C62-64 \| 688-722
Elongation at Break Percentage	20%	N/A
Modulus of Elasticity	31,000 ksi	31,000 ksi
Poisson's Ratio	0.30	0.30
Machinability Percentage	95%	N/A
Melting Point	2,580-2,660 °F	2,580-2,660 °F
Specific Heat	1.1 x 10^-1 BTU/lb-°F	1.1 x 10^-1 BTU/lb-°F
Thermal Conductivity	300 BTU-in/hr-ft^2-°F	300 BTU-in/hr-ft^2-°F
Electrical Conductivity	7.4% IACS	7.4% IACS

Chemistry Information
Element	Percentage
C	0.94
Fe	96.56
Cr	0.5
Mn	1.2
Si	0.3
W	0.5

Open for Orders 24/7!