R30035 Cobalt vs. S21800 Stainless Steel
R30035 cobalt belongs to the cobalt alloys classification, while S21800 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 25 material properties with values for both materials. Properties with values for just one material (10, in this case) are not shown.
For each property being compared, the top bar is R30035 cobalt and the bottom bar is S21800 stainless steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 220 to 230 | |
| 190 |
| Elongation at Break, % | 9.0 to 46 | |
| 40 |
| Fatigue Strength, MPa | 170 to 740 | |
| 330 |
| Poisson's Ratio | 0.29 | |
| 0.28 |
| Reduction in Area, % | 40 to 74 | |
| 62 |
| Shear Modulus, GPa | 84 to 89 | |
| 75 |
| Tensile Strength: Ultimate (UTS), MPa | 900 to 1900 | |
| 740 |
| Tensile Strength: Yield (Proof), MPa | 300 to 1650 | |
| 390 |
Thermal Properties
| Latent Heat of Fusion, J/g | 320 | |
| 340 |
| Melting Completion (Liquidus), °C | 1440 | |
| 1360 |
| Melting Onset (Solidus), °C | 1320 | |
| 1310 |
| Specific Heat Capacity, J/kg-K | 440 | |
| 500 |
| Thermal Expansion, µm/m-K | 13 | |
| 16 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 100 | |
| 15 |
| Density, g/cm3 | 8.7 | |
| 7.5 |
| Embodied Carbon, kg CO2/kg material | 10 | |
| 3.1 |
| Embodied Energy, MJ/kg | 140 | |
| 45 |
| Embodied Water, L/kg | 410 | |
| 150 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 160 to 320 | |
| 250 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 210 to 5920 | |
| 390 |
| Stiffness to Weight: Axial, points | 14 to 15 | |
| 14 |
| Stiffness to Weight: Bending, points | 23 to 24 | |
| 26 |
| Strength to Weight: Axial, points | 29 to 61 | |
| 27 |
| Strength to Weight: Bending, points | 24 to 39 | |
| 24 |
| Thermal Shock Resistance, points | 23 to 46 | |
| 17 |
Alloy Composition
| Boron (B), % | 0 to 0.015 | |
| 0 |
| Carbon (C), % | 0 to 0.025 | |
| 0 to 0.1 |
| Chromium (Cr), % | 19 to 21 | |
| 16 to 18 |
| Cobalt (Co), % | 29.1 to 39 | |
| 0 |
| Iron (Fe), % | 0 to 1.0 | |
| 59.1 to 65.4 |
| Manganese (Mn), % | 0 to 0.15 | |
| 7.0 to 9.0 |
| Molybdenum (Mo), % | 9.0 to 10.5 | |
| 0 |
| Nickel (Ni), % | 33 to 37 | |
| 8.0 to 9.0 |
| Nitrogen (N), % | 0 | |
| 0.080 to 0.18 |
| Phosphorus (P), % | 0 to 0.015 | |
| 0 to 0.060 |
| Silicon (Si), % | 0 to 0.15 | |
| 3.5 to 4.5 |
| Sulfur (S), % | 0 to 0.010 | |
| 0 to 0.030 |
| Titanium (Ti), % | 0 to 1.0 | |
| 0 |