R30155 Cobalt vs. EN 1.7231 Steel
Both R30155 cobalt and EN 1.7231 steel are iron alloys. They have a modest 33% of their average alloy composition in common, which, by itself, doesn't mean much. There are 28 material properties with values for both materials. Properties with values for just one material (7, in this case) are not shown.
For each property being compared, the top bar is R30155 cobalt and the bottom bar is EN 1.7231 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 220 | |
| 240 to 280 |
| Elastic (Young's, Tensile) Modulus, GPa | 210 | |
| 190 |
| Elongation at Break, % | 34 | |
| 11 to 12 |
| Fatigue Strength, MPa | 310 | |
| 360 to 500 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 81 | |
| 73 |
| Tensile Strength: Ultimate (UTS), MPa | 850 | |
| 790 to 930 |
| Tensile Strength: Yield (Proof), MPa | 390 | |
| 570 to 800 |
Thermal Properties
| Latent Heat of Fusion, J/g | 300 | |
| 250 |
| Maximum Temperature: Mechanical, °C | 1100 | |
| 420 |
| Melting Completion (Liquidus), °C | 1470 | |
| 1460 |
| Melting Onset (Solidus), °C | 1420 | |
| 1420 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 470 |
| Thermal Conductivity, W/m-K | 12 | |
| 46 |
| Thermal Expansion, µm/m-K | 14 | |
| 13 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 80 | |
| 2.5 |
| Density, g/cm3 | 8.5 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 9.7 | |
| 1.5 |
| Embodied Energy, MJ/kg | 150 | |
| 20 |
| Embodied Water, L/kg | 300 | |
| 51 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 230 | |
| 87 to 100 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 370 | |
| 870 to 1700 |
| Stiffness to Weight: Axial, points | 14 | |
| 13 |
| Stiffness to Weight: Bending, points | 23 | |
| 24 |
| Strength to Weight: Axial, points | 28 | |
| 28 to 33 |
| Strength to Weight: Bending, points | 24 | |
| 24 to 27 |
| Thermal Diffusivity, mm2/s | 3.2 | |
| 12 |
| Thermal Shock Resistance, points | 21 | |
| 23 to 27 |
Alloy Composition
| Carbon (C), % | 0.080 to 0.16 | |
| 0.38 to 0.45 |
| Chromium (Cr), % | 20 to 22.5 | |
| 0.8 to 1.2 |
| Cobalt (Co), % | 18.5 to 21 | |
| 0 |
| Iron (Fe), % | 24.3 to 36.2 | |
| 96.4 to 98.1 |
| Manganese (Mn), % | 1.0 to 2.0 | |
| 0.6 to 1.0 |
| Molybdenum (Mo), % | 2.5 to 3.5 | |
| 0.15 to 0.3 |
| Nickel (Ni), % | 19 to 21 | |
| 0 |
| Niobium (Nb), % | 0.75 to 1.3 | |
| 0 |
| Nitrogen (N), % | 0 to 0.2 | |
| 0 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.025 |
| Silicon (Si), % | 0 to 1.0 | |
| 0 to 0.6 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.030 |
| Tantalum (Ta), % | 0.75 to 1.3 | |
| 0 |
| Tungsten (W), % | 2.0 to 3.0 | |
| 0 |