SAE-AISI M3 Class 2 (T11323) Molybdenum High-Speed Steel

SAE-AISI M3 class 2 steel is a tool steel. M3 Class 2 is the designation in both the SAE and AISI systems for this material. T11323 is the UNS number.

The properties of SAE-AISI M3 class 2 steel include two common variations. This page shows summary ranges across both of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare SAE-AISI M3 class 2 steel to: tool steels (top), all iron alloys (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.

Annealed M3 Class 2 Tool Steel Hardened M3 Class 2 Tool Steel

Mechanical Properties

Elastic (Young's, Tensile) Modulus

200 GPa 29 x 10⁶ psi

Poisson's Ratio

0.29

Shear Modulus

77 GPa 11 x 10⁶ psi

Tensile Strength: Ultimate (UTS)

770 to 2210 MPa 110 to 320 x 10³ psi

Thermal Properties

Latent Heat of Fusion

260 J/g

Melting Completion (Liquidus)

1620 °C 2940 °F

Melting Onset (Solidus)

1570 °C 2850 °F

Specific Heat Capacity

440 J/kg-K 0.11 BTU/lb-°F

Thermal Conductivity

26 W/m-K 15 BTU/h-ft-°F

Thermal Expansion

12 µm/m-K

Otherwise Unclassified Properties

Base Metal Price

25 % relative

Density

8.3 g/cm³ 520 lb/ft³

Embodied Carbon

12 kg CO₂/kg material

Embodied Energy

180 MJ/kg 78 x 10³ BTU/lb

Embodied Water

110 L/kg 13 gal/lb

Common Calculations

PREN (Pitting Resistance)

Stiffness to Weight: Axial

13 points

Stiffness to Weight: Bending

23 points

Strength to Weight: Axial

26 to 74 points

Strength to Weight: Bending

22 to 45 points

Thermal Diffusivity

7.2 mm²/s

Thermal Shock Resistance

24 to 69 points

Alloy Composition

Iron (Fe)Fe		75.8 to 82.3
Tungsten (W)W		5.0 to 6.8
Molybdenum (Mo)Mo		4.8 to 6.5
Chromium (Cr)Cr		3.8 to 4.5
Vanadium (V)V		2.8 to 3.8
Carbon (C)C		1.2 to 1.3
Silicon (Si)Si		0.2 to 0.45
Manganese (Mn)Mn		0.15 to 0.4
Nickel (Ni)Ni		0 to 0.3
Copper (Cu)Cu		0 to 0.25
Phosphorus (P)P		0 to 0.030
Sulfur (S)S		0 to 0.030