R30021 Cobalt vs. AISI 304L Stainless Steel
R30021 cobalt belongs to the cobalt alloys classification, while AISI 304L stainless steel belongs to the iron alloys. They have a modest 23% of their average alloy composition in common, which, by itself, doesn't mean much. There are 27 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 R30021 cobalt and the bottom bar is AISI 304L stainless steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 220 | |
| 200 |
| Elongation at Break, % | 9.0 | |
| 6.7 to 46 |
| Fatigue Strength, MPa | 250 | |
| 170 to 430 |
| Poisson's Ratio | 0.29 | |
| 0.28 |
| Shear Modulus, GPa | 86 | |
| 77 |
| Tensile Strength: Ultimate (UTS), MPa | 700 | |
| 540 to 1160 |
| Tensile Strength: Yield (Proof), MPa | 500 | |
| 190 to 870 |
Thermal Properties
| Latent Heat of Fusion, J/g | 330 | |
| 290 |
| Melting Completion (Liquidus), °C | 1350 | |
| 1450 |
| Melting Onset (Solidus), °C | 1190 | |
| 1400 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 480 |
| Thermal Conductivity, W/m-K | 15 | |
| 16 |
| Thermal Expansion, µm/m-K | 11 | |
| 17 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 1.9 | |
| 2.4 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 2.1 | |
| 2.7 |
Otherwise Unclassified Properties
| Density, g/cm3 | 8.4 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 8.0 | |
| 3.1 |
| Embodied Energy, MJ/kg | 110 | |
| 44 |
| Embodied Water, L/kg | 520 | |
| 150 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 57 | |
| 71 to 240 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 570 | |
| 92 to 1900 |
| Stiffness to Weight: Axial, points | 15 | |
| 14 |
| Stiffness to Weight: Bending, points | 24 | |
| 25 |
| Strength to Weight: Axial, points | 23 | |
| 19 to 41 |
| Strength to Weight: Bending, points | 21 | |
| 19 to 31 |
| Thermal Diffusivity, mm2/s | 3.8 | |
| 4.2 |
| Thermal Shock Resistance, points | 21 | |
| 12 to 25 |
Alloy Composition
| Carbon (C), % | 0.2 to 0.35 | |
| 0 to 0.030 |
| Chromium (Cr), % | 26 to 29 | |
| 18 to 20 |
| Cobalt (Co), % | 61.7 to 67.3 | |
| 0 |
| Iron (Fe), % | 0 to 3.0 | |
| 65 to 74 |
| Manganese (Mn), % | 0 | |
| 0 to 2.0 |
| Molybdenum (Mo), % | 4.5 to 6.0 | |
| 0 |
| Nickel (Ni), % | 2.0 to 3.0 | |
| 8.0 to 12 |
| Nitrogen (N), % | 0 | |
| 0 to 0.1 |
| Phosphorus (P), % | 0 | |
| 0 to 0.045 |
| Silicon (Si), % | 0 to 1.5 | |
| 0 to 0.75 |
| Sulfur (S), % | 0 | |
| 0 to 0.030 |