R30021 Cobalt vs. EN 1.4945 Stainless Steel
R30021 cobalt belongs to the cobalt alloys classification, while EN 1.4945 stainless steel belongs to the iron alloys. They have a modest 21% 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 (8, in this case) are not shown.
For each property being compared, the top bar is R30021 cobalt and the bottom bar is EN 1.4945 stainless steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 220 | |
| 200 |
| Elongation at Break, % | 9.0 | |
| 19 to 34 |
| Fatigue Strength, MPa | 250 | |
| 230 to 350 |
| Poisson's Ratio | 0.29 | |
| 0.28 |
| Shear Modulus, GPa | 86 | |
| 77 |
| Tensile Strength: Ultimate (UTS), MPa | 700 | |
| 640 to 740 |
| Tensile Strength: Yield (Proof), MPa | 500 | |
| 290 to 550 |
Thermal Properties
| Latent Heat of Fusion, J/g | 330 | |
| 290 |
| Melting Completion (Liquidus), °C | 1350 | |
| 1490 |
| Melting Onset (Solidus), °C | 1190 | |
| 1440 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 470 |
| Thermal Conductivity, W/m-K | 15 | |
| 14 |
| Thermal Expansion, µm/m-K | 11 | |
| 17 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 1.9 | |
| 2.9 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 2.1 | |
| 3.2 |
Otherwise Unclassified Properties
| Density, g/cm3 | 8.4 | |
| 8.1 |
| Embodied Carbon, kg CO2/kg material | 8.0 | |
| 5.0 |
| Embodied Energy, MJ/kg | 110 | |
| 73 |
| Embodied Water, L/kg | 520 | |
| 150 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 57 | |
| 130 to 180 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 570 | |
| 210 to 760 |
| Stiffness to Weight: Axial, points | 15 | |
| 14 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 23 | |
| 22 to 25 |
| Strength to Weight: Bending, points | 21 | |
| 20 to 22 |
| Thermal Diffusivity, mm2/s | 3.8 | |
| 3.7 |
| Thermal Shock Resistance, points | 21 | |
| 14 to 16 |
Alloy Composition
| Carbon (C), % | 0.2 to 0.35 | |
| 0.040 to 0.1 |
| Chromium (Cr), % | 26 to 29 | |
| 15.5 to 17.5 |
| Cobalt (Co), % | 61.7 to 67.3 | |
| 0 |
| Iron (Fe), % | 0 to 3.0 | |
| 57.9 to 65.7 |
| Manganese (Mn), % | 0 | |
| 0 to 1.5 |
| Molybdenum (Mo), % | 4.5 to 6.0 | |
| 0 |
| Nickel (Ni), % | 2.0 to 3.0 | |
| 15.5 to 17.5 |
| Niobium (Nb), % | 0 | |
| 0.4 to 1.2 |
| Nitrogen (N), % | 0 | |
| 0.060 to 0.14 |
| Phosphorus (P), % | 0 | |
| 0 to 0.035 |
| Silicon (Si), % | 0 to 1.5 | |
| 0.3 to 0.6 |
| Sulfur (S), % | 0 | |
| 0 to 0.015 |
| Tungsten (W), % | 0 | |
| 2.5 to 3.5 |