EN 1.7725 Steel vs. R30816 Cobalt
EN 1.7725 steel belongs to the iron alloys classification, while R30816 cobalt belongs to the cobalt alloys. There are 26 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 EN 1.7725 steel and the bottom bar is R30816 cobalt.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 250 to 300 | |
| 280 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 210 |
| Elongation at Break, % | 14 | |
| 23 |
| Fatigue Strength, MPa | 390 to 550 | |
| 250 |
| Poisson's Ratio | 0.29 | |
| 0.3 |
| Shear Modulus, GPa | 73 | |
| 81 |
| Tensile Strength: Ultimate (UTS), MPa | 830 to 1000 | |
| 1020 |
| Tensile Strength: Yield (Proof), MPa | 610 to 860 | |
| 460 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 300 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1540 |
| Melting Onset (Solidus), °C | 1420 | |
| 1460 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 420 |
| Thermal Conductivity, W/m-K | 39 | |
| 13 |
| Thermal Expansion, µm/m-K | 13 | |
| 12 |
Otherwise Unclassified Properties
| Density, g/cm3 | 7.8 | |
| 9.1 |
| Embodied Carbon, kg CO2/kg material | 1.8 | |
| 20 |
| Embodied Energy, MJ/kg | 24 | |
| 320 |
| Embodied Water, L/kg | 54 | |
| 440 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 110 to 130 | |
| 190 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 980 to 1940 | |
| 510 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 22 |
| Strength to Weight: Axial, points | 29 to 35 | |
| 31 |
| Strength to Weight: Bending, points | 25 to 28 | |
| 25 |
| Thermal Diffusivity, mm2/s | 11 | |
| 3.3 |
| Thermal Shock Resistance, points | 24 to 29 | |
| 28 |
Alloy Composition
| Carbon (C), % | 0.27 to 0.34 | |
| 0.32 to 0.42 |
| Chromium (Cr), % | 1.3 to 1.7 | |
| 19 to 21 |
| Cobalt (Co), % | 0 | |
| 40 to 49.8 |
| Iron (Fe), % | 95.7 to 97.5 | |
| 0 to 5.0 |
| Manganese (Mn), % | 0.6 to 1.0 | |
| 1.0 to 2.0 |
| Molybdenum (Mo), % | 0.3 to 0.5 | |
| 3.5 to 4.5 |
| Nickel (Ni), % | 0 | |
| 19 to 21 |
| Niobium (Nb), % | 0 | |
| 3.5 to 4.5 |
| Phosphorus (P), % | 0 to 0.025 | |
| 0 to 0.040 |
| Silicon (Si), % | 0 to 0.6 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.030 |
| Tantalum (Ta), % | 0 | |
| 3.5 to 4.5 |
| Tungsten (W), % | 0 | |
| 3.5 to 4.5 |
| Vanadium (V), % | 0.050 to 0.15 | |
| 0 |