Normalized 4320 Ni-Cr-Mo Steel
Normalized SAE-AISI 4320 is SAE-AISI 4320 steel in the normalized condition. The graph bars on the material properties cards below compare normalized SAE-AISI 4320 to: SAE-AISI wrought 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
Brinell Hardness
240
Elastic (Young's, Tensile) Modulus
190 GPa 27 x 106 psi
Elongation at Break
21 %
Fatigue Strength
320 MPa 47 x 103 psi
Poisson's Ratio
0.29
Shear Modulus
73 GPa 11 x 106 psi
Shear Strength
500 MPa 72 x 103 psi
Tensile Strength: Ultimate (UTS)
790 MPa 110 x 103 psi
Tensile Strength: Yield (Proof)
460 MPa 67 x 103 psi
Thermal Properties
Latent Heat of Fusion
250 J/g
Maximum Temperature: Mechanical
420 °C 790 °F
Melting Completion (Liquidus)
1460 °C 2660 °F
Melting Onset (Solidus)
1420 °C 2590 °F
Specific Heat Capacity
470 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
46 W/m-K 27 BTU/h-ft-°F
Thermal Expansion
11 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
3.4 % relative
Density
7.9 g/cm3 490 lb/ft3
Embodied Carbon
1.7 kg CO2/kg material
Embodied Energy
22 MJ/kg 9.4 x 103 BTU/lb
Embodied Water
52 L/kg 6.2 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
140 MJ/m3
Resilience: Unit (Modulus of Resilience)
560 kJ/m3
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
24 points
Strength to Weight: Axial
28 points
Strength to Weight: Bending
24 points
Thermal Diffusivity
13 mm2/s
Thermal Shock Resistance
27 points
Alloy Composition
| Fe | 95.8 to 97 | |
| Ni | 1.7 to 2.0 | |
| Mn | 0.45 to 0.65 | |
| Cr | 0.4 to 0.6 | |
| Si | 0.15 to 0.35 | |
| Mo | 0.2 to 0.3 | |
| C | 0.17 to 0.22 | |
| S | 0 to 0.040 | |
| P | 0 to 0.035 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Further Reading
ASM Specialty Handbook: Carbon and Alloy Steels, J. R. Davis (editor), 1996
Manufacture and Uses of Alloy Steels, Henry D. Hibbard, 2005
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015
Steels: Processing, Structure, and Performance, 2nd ed., George Krauss, 2015