SAE-AISI 4320 Steel vs. ASTM A372 Grade M Steel
Both SAE-AISI 4320 steel and ASTM A372 grade M steel are iron alloys. They have a very high 97% of their average alloy composition in common. There are 31 material properties with values for both materials. Properties with values for just one material (1, in this case) are not shown.
For each property being compared, the top bar is SAE-AISI 4320 steel and the bottom bar is ASTM A372 grade M steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 160 to 240 | |
| 240 to 280 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 21 to 29 | |
| 18 to 21 |
| Fatigue Strength, MPa | 320 | |
| 450 to 520 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 73 | |
| 73 |
| Shear Strength, MPa | 370 to 500 | |
| 510 to 570 |
| Tensile Strength: Ultimate (UTS), MPa | 570 to 790 | |
| 810 to 910 |
| Tensile Strength: Yield (Proof), MPa | 430 to 460 | |
| 660 to 770 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 250 |
| Maximum Temperature: Mechanical, °C | 420 | |
| 450 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1460 |
| Melting Onset (Solidus), °C | 1420 | |
| 1420 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 470 |
| Thermal Conductivity, W/m-K | 46 | |
| 46 |
| Thermal Expansion, µm/m-K | 11 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.4 | |
| 8.0 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.5 | |
| 9.1 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 3.4 | |
| 5.0 |
| Density, g/cm3 | 7.9 | |
| 7.9 |
| Embodied Carbon, kg CO2/kg material | 1.7 | |
| 2.0 |
| Embodied Energy, MJ/kg | 22 | |
| 27 |
| Embodied Water, L/kg | 52 | |
| 61 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 140 to 150 | |
| 160 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 480 to 560 | |
| 1140 to 1580 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 20 to 28 | |
| 29 to 32 |
| Strength to Weight: Bending, points | 19 to 24 | |
| 24 to 27 |
| Thermal Diffusivity, mm2/s | 13 | |
| 12 |
| Thermal Shock Resistance, points | 19 to 27 | |
| 24 to 27 |
Alloy Composition
| Carbon (C), % | 0.17 to 0.22 | |
| 0 to 0.23 |
| Chromium (Cr), % | 0.4 to 0.6 | |
| 1.5 to 2.0 |
| Iron (Fe), % | 95.8 to 97 | |
| 92.5 to 95.1 |
| Manganese (Mn), % | 0.45 to 0.65 | |
| 0.2 to 0.4 |
| Molybdenum (Mo), % | 0.2 to 0.3 | |
| 0.4 to 0.6 |
| Nickel (Ni), % | 1.7 to 2.0 | |
| 2.8 to 3.9 |
| Phosphorus (P), % | 0 to 0.035 | |
| 0 to 0.015 |
| Silicon (Si), % | 0.15 to 0.35 | |
| 0 to 0.3 |
| Sulfur (S), % | 0 to 0.040 | |
| 0 to 0.010 |
| Vanadium (V), % | 0 | |
| 0 to 0.080 |