ASTM A387 Grade 21 Steel vs. Grade 363 Molybdenum
ASTM A387 grade 21 steel belongs to the iron alloys classification, while grade 363 molybdenum belongs to the otherwise unclassified metals. There are 20 material properties with values for both materials. Properties with values for just one material (12, in this case) are not shown.
For each property being compared, the top bar is ASTM A387 grade 21 steel and the bottom bar is grade 363 molybdenum.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 310 |
| Elongation at Break, % | 21 | |
| 6.2 to 11 |
| Poisson's Ratio | 0.29 | |
| 0.31 |
| Shear Modulus, GPa | 74 | |
| 120 |
| Tensile Strength: Ultimate (UTS), MPa | 500 to 590 | |
| 580 to 720 |
| Tensile Strength: Yield (Proof), MPa | 230 to 350 | |
| 350 to 620 |
Thermal Properties
| Latent Heat of Fusion, J/g | 260 | |
| 370 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 250 |
| Thermal Expansion, µm/m-K | 13 | |
| 7.0 |
Otherwise Unclassified Properties
| Density, g/cm3 | 7.9 | |
| 10 |
| Embodied Carbon, kg CO2/kg material | 1.8 | |
| 28 |
| Embodied Energy, MJ/kg | 23 | |
| 330 |
| Embodied Water, L/kg | 62 | |
| 360 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 84 to 110 | |
| 43 to 57 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 140 to 320 | |
| 200 to 630 |
| Stiffness to Weight: Axial, points | 13 | |
| 17 |
| Stiffness to Weight: Bending, points | 24 | |
| 22 |
| Strength to Weight: Axial, points | 18 to 21 | |
| 16 to 20 |
| Strength to Weight: Bending, points | 18 to 20 | |
| 15 to 17 |
| Thermal Shock Resistance, points | 14 to 17 | |
| 19 to 24 |
Alloy Composition
| Carbon (C), % | 0.050 to 0.15 | |
| 0.010 to 0.030 |
| Chromium (Cr), % | 2.8 to 3.3 | |
| 0 |
| Iron (Fe), % | 94.4 to 96 | |
| 0 to 0.010 |
| Manganese (Mn), % | 0.3 to 0.6 | |
| 0 |
| Molybdenum (Mo), % | 0.9 to 1.1 | |
| 99.3 to 99.5 |
| Nickel (Ni), % | 0 | |
| 0 to 0.0020 |
| Nitrogen (N), % | 0 | |
| 0 to 0.0020 |
| Oxygen (O), % | 0 | |
| 0 to 0.0030 |
| Phosphorus (P), % | 0 to 0.025 | |
| 0 |
| Silicon (Si), % | 0 to 0.5 | |
| 0 to 0.010 |
| Sulfur (S), % | 0 to 0.025 | |
| 0 |
| Titanium (Ti), % | 0 | |
| 0.4 to 0.55 |
| Zirconium (Zr), % | 0 | |
| 0.060 to 0.12 |