ASTM A387 Grade 12 Steel vs. R30816 Cobalt
ASTM A387 grade 12 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 ASTM A387 grade 12 steel and the bottom bar is R30816 cobalt.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 140 to 160 | |
| 280 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 210 |
| Elongation at Break, % | 25 | |
| 23 |
| Fatigue Strength, MPa | 190 to 230 | |
| 250 |
| Poisson's Ratio | 0.29 | |
| 0.3 |
| Shear Modulus, GPa | 73 | |
| 81 |
| Tensile Strength: Ultimate (UTS), MPa | 470 to 520 | |
| 1020 |
| Tensile Strength: Yield (Proof), MPa | 260 to 310 | |
| 460 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 300 |
| Melting Completion (Liquidus), °C | 1470 | |
| 1540 |
| Melting Onset (Solidus), °C | 1420 | |
| 1460 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 420 |
| Thermal Conductivity, W/m-K | 44 | |
| 13 |
| Thermal Expansion, µm/m-K | 13 | |
| 12 |
Otherwise Unclassified Properties
| Density, g/cm3 | 7.8 | |
| 9.1 |
| Embodied Carbon, kg CO2/kg material | 1.6 | |
| 20 |
| Embodied Energy, MJ/kg | 21 | |
| 320 |
| Embodied Water, L/kg | 51 | |
| 440 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 98 to 110 | |
| 190 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 180 to 250 | |
| 510 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 22 |
| Strength to Weight: Axial, points | 16 to 18 | |
| 31 |
| Strength to Weight: Bending, points | 17 to 18 | |
| 25 |
| Thermal Diffusivity, mm2/s | 12 | |
| 3.3 |
| Thermal Shock Resistance, points | 14 to 15 | |
| 28 |
Alloy Composition
| Carbon (C), % | 0.050 to 0.17 | |
| 0.32 to 0.42 |
| Chromium (Cr), % | 0.8 to 1.2 | |
| 19 to 21 |
| Cobalt (Co), % | 0 | |
| 40 to 49.8 |
| Iron (Fe), % | 97 to 98.2 | |
| 0 to 5.0 |
| Manganese (Mn), % | 0.4 to 0.65 | |
| 1.0 to 2.0 |
| Molybdenum (Mo), % | 0.45 to 0.6 | |
| 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), % | 0.15 to 0.4 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 to 0.025 | |
| 0 to 0.030 |
| Tantalum (Ta), % | 0 | |
| 3.5 to 4.5 |
| Tungsten (W), % | 0 | |
| 3.5 to 4.5 |