Hardened D7 Tool Steel
Hardened SAE-AISI D7 is SAE-AISI D7 steel in the hardened (H) condition. The graph bars on the material properties cards below compare hardened SAE-AISI D7 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
0.28
Rockwell C Hardness
65
Shear Modulus
73 GPa 11 x 106 psi
Tensile Strength: Ultimate (UTS)
2120 MPa 310 x 103 psi
Thermal Properties
Latent Heat of Fusion
270 J/g
Melting Completion (Liquidus)
1440 °C 2620 °F
Melting Onset (Solidus)
1400 °C 2540 °F
Specific Heat Capacity
480 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
27 W/m-K 15 BTU/h-ft-°F
Thermal Expansion
11 µm/m-K
Otherwise Unclassified Properties
Base Metal Price
10 % relative
Density
7.6 g/cm3 470 lb/ft3
Embodied Carbon
11 kg CO2/kg material
Embodied Energy
180 MJ/kg 78 x 103 BTU/lb
Embodied Water
130 L/kg 15 gal/lb
Common Calculations
PREN (Pitting Resistance)
16
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
78 points
Strength to Weight: Bending
48 points
Thermal Diffusivity
7.4 mm2/s
Thermal Shock Resistance
72 points
Alloy Composition
| Fe | 76.6 to 81.9 | |
| Cr | 11.5 to 13.5 | |
| V | 3.8 to 4.4 | |
| C | 2.2 to 2.5 | |
| Mo | 0.7 to 1.2 | |
| Mn | 0 to 0.6 | |
| Si | 0 to 0.6 | |
| Ni | 0 to 0.3 | |
| 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
Further Reading
SAE J437: Selection and Heat Treatment of Tool and Die Steels
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