R30021 Cobalt vs. SAE-AISI M48 Steel
R30021 cobalt belongs to the cobalt alloys classification, while SAE-AISI M48 steel belongs to the iron alloys. They have a modest 20% of their average alloy composition in common, which, by itself, doesn't mean much. There are 18 material properties with values for both materials. Properties with values for just one material (13, in this case) are not shown.
For each property being compared, the top bar is R30021 cobalt and the bottom bar is SAE-AISI M48 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 220 | |
| 200 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 86 | |
| 78 |
| Tensile Strength: Ultimate (UTS), MPa | 700 | |
| 890 to 2390 |
Thermal Properties
| Latent Heat of Fusion, J/g | 330 | |
| 260 |
| Melting Completion (Liquidus), °C | 1350 | |
| 1670 |
| Melting Onset (Solidus), °C | 1190 | |
| 1620 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 420 |
| Thermal Expansion, µm/m-K | 11 | |
| 12 |
Otherwise Unclassified Properties
| Density, g/cm3 | 8.4 | |
| 8.7 |
| Embodied Carbon, kg CO2/kg material | 8.0 | |
| 13 |
| Embodied Energy, MJ/kg | 110 | |
| 190 |
| Embodied Water, L/kg | 520 | |
| 160 |
Common Calculations
| Stiffness to Weight: Axial, points | 15 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 22 |
| Strength to Weight: Axial, points | 23 | |
| 28 to 76 |
| Strength to Weight: Bending, points | 21 | |
| 23 to 45 |
| Thermal Shock Resistance, points | 21 | |
| 26 to 71 |
Alloy Composition
| Carbon (C), % | 0.2 to 0.35 | |
| 1.4 to 1.5 |
| Chromium (Cr), % | 26 to 29 | |
| 3.5 to 4.0 |
| Cobalt (Co), % | 61.7 to 67.3 | |
| 8.0 to 10 |
| Copper (Cu), % | 0 | |
| 0 to 0.25 |
| Iron (Fe), % | 0 to 3.0 | |
| 63.8 to 69.8 |
| Manganese (Mn), % | 0 | |
| 0.15 to 0.4 |
| Molybdenum (Mo), % | 4.5 to 6.0 | |
| 4.8 to 5.5 |
| Nickel (Ni), % | 2.0 to 3.0 | |
| 0 to 0.3 |
| Phosphorus (P), % | 0 | |
| 0 to 0.030 |
| Silicon (Si), % | 0 to 1.5 | |
| 0.15 to 0.4 |
| Sulfur (S), % | 0 | |
| 0 to 0.030 |
| Tungsten (W), % | 0 | |
| 9.5 to 10.5 |
| Vanadium (V), % | 0 | |
| 2.8 to 3.3 |