SAE-AISI P20 (T51620) Low-Carbon Mould Steel
SAE-AISI P20 steel is a tool steel. P20 is the designation in both the SAE and AISI systems for this material. T51620 is the UNS number.
The properties of SAE-AISI P20 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 P20 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.
Mechanical Properties
Elastic (Young's, Tensile) Modulus
190 GPa 27 x 106 psi
Poisson's Ratio
0.29
Shear Modulus
73 GPa 11 x 106 psi
Tensile Strength: Ultimate (UTS)
540 to 1050 MPa 79 to 150 x 103 psi
Thermal Properties
Latent Heat of Fusion
260 J/g
Melting Completion (Liquidus)
1460 °C 2660 °F
Melting Onset (Solidus)
1420 °C 2580 °F
Specific Heat Capacity
470 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
45 W/m-K 26 BTU/h-ft-°F
Thermal Expansion
12 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
7.4 % IACS
Electrical Conductivity: Equal Weight (Specific)
8.5 % IACS
Otherwise Unclassified Properties
Base Metal Price
2.8 % relative
Density
7.8 g/cm3 490 lb/ft3
Embodied Carbon
1.6 kg CO2/kg material
Embodied Energy
21 MJ/kg 8.9 x 103 BTU/lb
Embodied Water
52 L/kg 6.2 gal/lb
Common Calculations
PREN (Pitting Resistance)
2.6
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
19 to 37 points
Strength to Weight: Bending
19 to 29 points
Thermal Diffusivity
12 mm2/s
Thermal Shock Resistance
18 to 35 points
Alloy Composition
Fe | 95.2 to 98.5 | |
Cr | 0.4 to 2.0 | |
Mn | 0.35 to 0.71 | |
Si | 0.2 to 0.8 | |
Mo | 0.3 to 0.55 | |
C | 0.28 to 0.4 | |
Cu | 0 to 0.25 | |
P | 0 to 0.030 | |
S | 0 to 0.030 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM A681: Standard Specification for Tool Steels Alloy
Tool Steels, 5th ed., George Roberts et al., 1998
Tool Steels: Properties and Performance, Rafael A. Mesquita (editor), 2016
ASM Specialty Handbook: Carbon and Alloy Steels, J. R. Davis (editor), 1996
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015