R31539 Cobalt vs. S20910 Stainless Steel
R31539 cobalt belongs to the cobalt alloys classification, while S20910 stainless steel belongs to the iron alloys. They have a modest 26% of their average alloy composition in common, which, by itself, doesn't mean much. There are 26 material properties with values for both materials. Properties with values for just one material (9, in this case) are not shown.
For each property being compared, the top bar is R31539 cobalt and the bottom bar is S20910 stainless steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 220 | |
| 200 |
| Elongation at Break, % | 13 to 22 | |
| 14 to 39 |
| Fatigue Strength, MPa | 310 to 480 | |
| 310 to 460 |
| Poisson's Ratio | 0.29 | |
| 0.28 |
| Reduction in Area, % | 13 to 23 | |
| 56 to 62 |
| Shear Modulus, GPa | 86 | |
| 79 |
| Tensile Strength: Ultimate (UTS), MPa | 1000 to 1340 | |
| 780 to 940 |
| Tensile Strength: Yield (Proof), MPa | 590 to 940 | |
| 430 to 810 |
Thermal Properties
| Latent Heat of Fusion, J/g | 320 | |
| 300 |
| Melting Completion (Liquidus), °C | 1360 | |
| 1420 |
| Melting Onset (Solidus), °C | 1290 | |
| 1380 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 480 |
| Thermal Conductivity, W/m-K | 13 | |
| 13 |
| Thermal Expansion, µm/m-K | 13 | |
| 16 |
Otherwise Unclassified Properties
| Density, g/cm3 | 8.4 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 8.2 | |
| 4.8 |
| Embodied Energy, MJ/kg | 110 | |
| 68 |
| Embodied Water, L/kg | 530 | |
| 180 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 140 to 190 | |
| 120 to 260 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 780 to 2000 | |
| 460 to 1640 |
| Stiffness to Weight: Axial, points | 15 | |
| 14 |
| Stiffness to Weight: Bending, points | 24 | |
| 25 |
| Strength to Weight: Axial, points | 33 to 44 | |
| 28 to 33 |
| Strength to Weight: Bending, points | 27 to 32 | |
| 24 to 27 |
| Thermal Diffusivity, mm2/s | 3.5 | |
| 3.6 |
| Thermal Shock Resistance, points | 24 to 32 | |
| 17 to 21 |
Alloy Composition
| Aluminum (Al), % | 0.3 to 1.0 | |
| 0 |
| Carbon (C), % | 0 to 0.14 | |
| 0 to 0.060 |
| Chromium (Cr), % | 26 to 30 | |
| 20.5 to 23.5 |
| Cobalt (Co), % | 57.7 to 68.7 | |
| 0 |
| Iron (Fe), % | 0 to 0.75 | |
| 52.1 to 62.1 |
| Lanthanum (La), % | 0.030 to 0.2 | |
| 0 |
| Manganese (Mn), % | 0 to 1.0 | |
| 4.0 to 6.0 |
| Molybdenum (Mo), % | 5.0 to 7.0 | |
| 1.5 to 3.0 |
| Nickel (Ni), % | 0 to 1.0 | |
| 11.5 to 13.5 |
| Niobium (Nb), % | 0 | |
| 0.1 to 0.3 |
| Nitrogen (N), % | 0 to 0.25 | |
| 0.2 to 0.4 |
| Phosphorus (P), % | 0 | |
| 0 to 0.040 |
| Silicon (Si), % | 0 to 1.0 | |
| 0 to 0.75 |
| Sulfur (S), % | 0 | |
| 0 to 0.030 |
| Vanadium (V), % | 0 | |
| 0.1 to 0.3 |