SAE-AISI 4340 Steel vs. Grade 366 Molybdenum
SAE-AISI 4340 steel belongs to the iron alloys classification, while grade 366 molybdenum belongs to the otherwise unclassified metals. There are 20 material properties with values for both materials. Properties with values for just one material (11, in this case) are not shown.
For each property being compared, the top bar is SAE-AISI 4340 steel and the bottom bar is grade 366 molybdenum.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 300 |
| Elongation at Break, % | 12 to 22 | |
| 2.2 |
| Poisson's Ratio | 0.29 | |
| 0.3 |
| Shear Modulus, GPa | 73 | |
| 120 |
| Tensile Strength: Ultimate (UTS), MPa | 690 to 1280 | |
| 580 |
| Tensile Strength: Yield (Proof), MPa | 470 to 1150 | |
| 470 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 310 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 210 |
| Thermal Expansion, µm/m-K | 13 | |
| 7.6 |
Otherwise Unclassified Properties
| Density, g/cm3 | 7.8 | |
| 12 |
| Embodied Carbon, kg CO2/kg material | 1.7 | |
| 27 |
| Embodied Energy, MJ/kg | 22 | |
| 340 |
| Embodied Water, L/kg | 53 | |
| 300 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 79 to 170 | |
| 12 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 590 to 3490 | |
| 370 |
| Stiffness to Weight: Axial, points | 13 | |
| 14 |
| Stiffness to Weight: Bending, points | 24 | |
| 18 |
| Strength to Weight: Axial, points | 24 to 45 | |
| 13 |
| Strength to Weight: Bending, points | 22 to 33 | |
| 13 |
| Thermal Shock Resistance, points | 20 to 38 | |
| 18 |
Alloy Composition
| Carbon (C), % | 0.38 to 0.43 | |
| 0 to 0.030 |
| Chromium (Cr), % | 0.7 to 0.9 | |
| 0 |
| Iron (Fe), % | 95.1 to 96.3 | |
| 0 to 0.010 |
| Manganese (Mn), % | 0.6 to 0.8 | |
| 0 |
| Molybdenum (Mo), % | 0.2 to 0.3 | |
| 66.9 to 73 |
| Nickel (Ni), % | 1.7 to 2.0 | |
| 0 to 0.0020 |
| Nitrogen (N), % | 0 | |
| 0 to 0.0020 |
| Oxygen (O), % | 0 | |
| 0 to 0.0025 |
| Phosphorus (P), % | 0 to 0.035 | |
| 0 |
| Silicon (Si), % | 0.15 to 0.35 | |
| 0 to 0.010 |
| Sulfur (S), % | 0 to 0.040 | |
| 0 |
| Tungsten (W), % | 0 | |
| 27 to 33 |