R31538 Cobalt vs. Grade 250 Maraging Steel
R31538 cobalt belongs to the cobalt alloys classification, while grade 250 maraging steel belongs to the iron alloys. There are 22 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 R31538 cobalt and the bottom bar is grade 250 maraging steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 220 | |
| 190 |
| Elongation at Break, % | 13 to 23 | |
| 7.3 to 17 |
| Poisson's Ratio | 0.29 | |
| 0.3 |
| Rockwell C Hardness | 25 to 35 | |
| 30 to 53 |
| Shear Modulus, GPa | 86 | |
| 75 |
| Tensile Strength: Ultimate (UTS), MPa | 1020 to 1360 | |
| 970 to 1800 |
| Tensile Strength: Yield (Proof), MPa | 580 to 930 | |
| 660 to 1740 |
Thermal Properties
| Latent Heat of Fusion, J/g | 320 | |
| 270 |
| Melting Completion (Liquidus), °C | 1360 | |
| 1480 |
| Melting Onset (Solidus), °C | 1290 | |
| 1430 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 450 |
| Thermal Expansion, µm/m-K | 13 | |
| 12 |
Otherwise Unclassified Properties
| Density, g/cm3 | 8.4 | |
| 8.2 |
| Embodied Carbon, kg CO2/kg material | 8.1 | |
| 4.9 |
| Embodied Energy, MJ/kg | 110 | |
| 65 |
| Embodied Water, L/kg | 530 | |
| 140 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 140 to 200 | |
| 130 to 150 |
| Stiffness to Weight: Axial, points | 15 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 23 |
| Strength to Weight: Axial, points | 34 to 45 | |
| 33 to 61 |
| Strength to Weight: Bending, points | 27 to 32 | |
| 26 to 40 |
| Thermal Shock Resistance, points | 25 to 33 | |
| 29 to 54 |
Alloy Composition
| Aluminum (Al), % | 0 | |
| 0.050 to 0.15 |
| Boron (B), % | 0 | |
| 0 to 0.0030 |
| Calcium (Ca), % | 0 | |
| 0 to 0.050 |
| Carbon (C), % | 0.15 to 0.35 | |
| 0 to 0.030 |
| Chromium (Cr), % | 26 to 30 | |
| 0 |
| Cobalt (Co), % | 58.7 to 68.9 | |
| 7.0 to 8.5 |
| Iron (Fe), % | 0 to 0.75 | |
| 66.3 to 71.1 |
| Manganese (Mn), % | 0 to 1.0 | |
| 0 to 0.1 |
| Molybdenum (Mo), % | 5.0 to 7.0 | |
| 4.6 to 5.2 |
| Nickel (Ni), % | 0 to 1.0 | |
| 17 to 19 |
| Nitrogen (N), % | 0 to 0.25 | |
| 0 |
| Phosphorus (P), % | 0 | |
| 0 to 0.010 |
| Silicon (Si), % | 0 to 1.0 | |
| 0 to 0.1 |
| Sulfur (S), % | 0 | |
| 0 to 0.010 |
| Titanium (Ti), % | 0 | |
| 0.3 to 0.5 |
| Zirconium (Zr), % | 0 | |
| 0 to 0.020 |