R30021 Cobalt vs. EN 1.4424 Stainless Steel
R30021 cobalt belongs to the cobalt alloys classification, while EN 1.4424 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 27 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 R30021 cobalt and the bottom bar is EN 1.4424 stainless steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 220 | |
| 200 |
| Elongation at Break, % | 9.0 | |
| 28 |
| Fatigue Strength, MPa | 250 | |
| 350 to 370 |
| Poisson's Ratio | 0.29 | |
| 0.28 |
| Shear Modulus, GPa | 86 | |
| 78 |
| Tensile Strength: Ultimate (UTS), MPa | 700 | |
| 800 |
| Tensile Strength: Yield (Proof), MPa | 500 | |
| 480 to 500 |
Thermal Properties
| Latent Heat of Fusion, J/g | 330 | |
| 310 |
| Melting Completion (Liquidus), °C | 1350 | |
| 1430 |
| Melting Onset (Solidus), °C | 1190 | |
| 1390 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 480 |
| Thermal Conductivity, W/m-K | 15 | |
| 13 |
| Thermal Expansion, µm/m-K | 11 | |
| 12 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 1.9 | |
| 2.2 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 2.1 | |
| 2.5 |
Otherwise Unclassified Properties
| Density, g/cm3 | 8.4 | |
| 7.7 |
| Embodied Carbon, kg CO2/kg material | 8.0 | |
| 3.4 |
| Embodied Energy, MJ/kg | 110 | |
| 46 |
| Embodied Water, L/kg | 520 | |
| 140 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 57 | |
| 190 to 200 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 570 | |
| 580 to 640 |
| Stiffness to Weight: Axial, points | 15 | |
| 14 |
| Stiffness to Weight: Bending, points | 24 | |
| 25 |
| Strength to Weight: Axial, points | 23 | |
| 29 |
| Strength to Weight: Bending, points | 21 | |
| 25 |
| Thermal Diffusivity, mm2/s | 3.8 | |
| 3.5 |
| Thermal Shock Resistance, points | 21 | |
| 23 |
Alloy Composition
| Carbon (C), % | 0.2 to 0.35 | |
| 0 to 0.030 |
| Chromium (Cr), % | 26 to 29 | |
| 18 to 19 |
| Cobalt (Co), % | 61.7 to 67.3 | |
| 0 |
| Iron (Fe), % | 0 to 3.0 | |
| 68.6 to 72.4 |
| Manganese (Mn), % | 0 | |
| 1.2 to 2.0 |
| Molybdenum (Mo), % | 4.5 to 6.0 | |
| 2.5 to 3.0 |
| Nickel (Ni), % | 2.0 to 3.0 | |
| 4.5 to 5.2 |
| Nitrogen (N), % | 0 | |
| 0.050 to 0.1 |
| Phosphorus (P), % | 0 | |
| 0 to 0.035 |
| Silicon (Si), % | 0 to 1.5 | |
| 1.4 to 2.0 |
| Sulfur (S), % | 0 | |
| 0 to 0.015 |