R30816 Cobalt vs. ASTM A387 Grade 2 Steel
R30816 cobalt belongs to the cobalt alloys classification, while ASTM A387 grade 2 steel belongs to the iron 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 R30816 cobalt and the bottom bar is ASTM A387 grade 2 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 280 | |
| 140 to 170 |
| Elastic (Young's, Tensile) Modulus, GPa | 210 | |
| 190 |
| Elongation at Break, % | 23 | |
| 25 |
| Fatigue Strength, MPa | 250 | |
| 190 to 250 |
| Poisson's Ratio | 0.3 | |
| 0.29 |
| Shear Modulus, GPa | 81 | |
| 73 |
| Tensile Strength: Ultimate (UTS), MPa | 1020 | |
| 470 to 550 |
| Tensile Strength: Yield (Proof), MPa | 460 | |
| 260 to 350 |
Thermal Properties
| Latent Heat of Fusion, J/g | 300 | |
| 250 |
| Melting Completion (Liquidus), °C | 1540 | |
| 1470 |
| Melting Onset (Solidus), °C | 1460 | |
| 1420 |
| Specific Heat Capacity, J/kg-K | 420 | |
| 470 |
| Thermal Conductivity, W/m-K | 13 | |
| 45 |
| Thermal Expansion, µm/m-K | 12 | |
| 13 |
Otherwise Unclassified Properties
| Density, g/cm3 | 9.1 | |
| 7.9 |
| Embodied Carbon, kg CO2/kg material | 20 | |
| 1.6 |
| Embodied Energy, MJ/kg | 320 | |
| 20 |
| Embodied Water, L/kg | 440 | |
| 50 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 190 | |
| 98 to 120 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 510 | |
| 180 to 320 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 22 | |
| 24 |
| Strength to Weight: Axial, points | 31 | |
| 16 to 20 |
| Strength to Weight: Bending, points | 25 | |
| 17 to 19 |
| Thermal Diffusivity, mm2/s | 3.3 | |
| 12 |
| Thermal Shock Resistance, points | 28 | |
| 14 to 16 |
Alloy Composition
| Carbon (C), % | 0.32 to 0.42 | |
| 0.050 to 0.21 |
| Chromium (Cr), % | 19 to 21 | |
| 0.5 to 0.8 |
| Cobalt (Co), % | 40 to 49.8 | |
| 0 |
| Iron (Fe), % | 0 to 5.0 | |
| 97.1 to 98.3 |
| Manganese (Mn), % | 1.0 to 2.0 | |
| 0.55 to 0.8 |
| Molybdenum (Mo), % | 3.5 to 4.5 | |
| 0.45 to 0.6 |
| Nickel (Ni), % | 19 to 21 | |
| 0 |
| Niobium (Nb), % | 3.5 to 4.5 | |
| 0 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.025 |
| Silicon (Si), % | 0 to 1.0 | |
| 0.15 to 0.4 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.025 |
| Tantalum (Ta), % | 3.5 to 4.5 | |
| 0 |
| Tungsten (W), % | 3.5 to 4.5 | |
| 0 |