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O1

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



O-1 Tool Steel Heat Treatment
Hardness
Heat Treat Temp.
Quench Medium
Applications
Disadvantages

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.

 

Physical Properties O1
 
Annealed
Hardened
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
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