Ductile Cast Iron vs. R30021 Cobalt
Ductile cast iron belongs to the iron alloys classification, while R30021 cobalt belongs to the cobalt alloys. There are 26 material properties with values for both materials. Properties with values for just one material (8, in this case) are not shown.
For each property being compared, the top bar is ductile cast iron and the bottom bar is R30021 cobalt.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 170 to 180 | |
| 220 |
| Elongation at Break, % | 2.1 to 20 | |
| 9.0 |
| Poisson's Ratio | 0.28 to 0.31 | |
| 0.29 |
| Shear Modulus, GPa | 64 to 70 | |
| 86 |
| Tensile Strength: Ultimate (UTS), MPa | 460 to 920 | |
| 700 |
| Tensile Strength: Yield (Proof), MPa | 310 to 670 | |
| 500 |
Thermal Properties
| Latent Heat of Fusion, J/g | 270 | |
| 330 |
| Melting Completion (Liquidus), °C | 1160 | |
| 1350 |
| Melting Onset (Solidus), °C | 1120 | |
| 1190 |
| Specific Heat Capacity, J/kg-K | 490 | |
| 450 |
| Thermal Conductivity, W/m-K | 31 to 36 | |
| 15 |
| Thermal Expansion, µm/m-K | 11 | |
| 11 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.4 | |
| 1.9 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.8 to 9.4 | |
| 2.1 |
Otherwise Unclassified Properties
| Density, g/cm3 | 7.1 to 7.5 | |
| 8.4 |
| Embodied Carbon, kg CO2/kg material | 1.5 | |
| 8.0 |
| Embodied Energy, MJ/kg | 21 | |
| 110 |
| Embodied Water, L/kg | 43 | |
| 520 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 17 to 80 | |
| 57 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 280 to 1330 | |
| 570 |
| Stiffness to Weight: Axial, points | 12 to 14 | |
| 15 |
| Stiffness to Weight: Bending, points | 24 to 26 | |
| 24 |
| Strength to Weight: Axial, points | 17 to 35 | |
| 23 |
| Strength to Weight: Bending, points | 18 to 29 | |
| 21 |
| Thermal Diffusivity, mm2/s | 8.9 to 10 | |
| 3.8 |
| Thermal Shock Resistance, points | 17 to 35 | |
| 21 |
Alloy Composition
| Carbon (C), % | 3.0 to 3.5 | |
| 0.2 to 0.35 |
| Chromium (Cr), % | 0 | |
| 26 to 29 |
| Cobalt (Co), % | 0 | |
| 61.7 to 67.3 |
| Iron (Fe), % | 93.7 to 95.5 | |
| 0 to 3.0 |
| Molybdenum (Mo), % | 0 | |
| 4.5 to 6.0 |
| Nickel (Ni), % | 0 | |
| 2.0 to 3.0 |
| Phosphorus (P), % | 0 to 0.080 | |
| 0 |
| Silicon (Si), % | 1.5 to 2.8 | |
| 0 to 1.5 |