SAE-AISI T4 (T12004) Tungsten High-Speed Steel

SAE-AISI T4 steel is a tool steel. T4 is the designation in both the SAE and AISI systems for this material. T12004 is the UNS number.

The properties of SAE-AISI T4 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 T4 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 T4 Tool Steel Hardened T4 Tool Steel

Mechanical Properties

Elastic (Young's, Tensile) Modulus

210 GPa 30 x 10⁶ psi

Poisson's Ratio

0.29

Shear Modulus

80 GPa 12 x 10⁶ psi

Tensile Strength: Ultimate (UTS)

800 to 2140 MPa 120 to 310 x 10³ psi

Thermal Properties

Latent Heat of Fusion

250 J/g

Melting Completion (Liquidus)

1810 °C 3280 °F

Melting Onset (Solidus)

1750 °C 3180 °F

Specific Heat Capacity

410 J/kg-K 0.1 BTU/lb-°F

Thermal Conductivity

21 W/m-K 12 BTU/h-ft-°F

Thermal Expansion

12 µm/m-K

Otherwise Unclassified Properties

Base Metal Price

55 % relative

Density

9.4 g/cm³ 580 lb/ft³

Embodied Carbon

8.5 kg CO₂/kg material

Embodied Energy

130 MJ/kg 56 x 10³ BTU/lb

Embodied Water

120 L/kg 14 gal/lb

Common Calculations

PREN (Pitting Resistance)

Stiffness to Weight: Axial

12 points

Stiffness to Weight: Bending

21 points

Strength to Weight: Axial

24 to 64 points

Strength to Weight: Bending

20 to 39 points

Thermal Diffusivity

5.4 mm²/s

Thermal Shock Resistance

24 to 64 points

Alloy Composition

Iron (Fe)Fe		66.3 to 72.3
Tungsten (W)W		17.5 to 19
Cobalt (Co)Co		4.3 to 5.8
Chromium (Cr)Cr		3.8 to 4.5
Vanadium (V)V		0.8 to 1.2
Carbon (C)C		0.7 to 0.8
Molybdenum (Mo)Mo		0.4 to 1.0
Silicon (Si)Si		0.2 to 0.4
Manganese (Mn)Mn		0.1 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