R30003 Cobalt vs. ASTM A372 Grade M Steel
R30003 cobalt belongs to the cobalt alloys classification, while ASTM A372 grade M 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 (5, in this case) are not shown.
For each property being compared, the top bar is R30003 cobalt and the bottom bar is ASTM A372 grade M steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 210 | |
| 190 |
| Elongation at Break, % | 10 to 73 | |
| 18 to 21 |
| Fatigue Strength, MPa | 320 to 560 | |
| 450 to 520 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 83 | |
| 73 |
| Tensile Strength: Ultimate (UTS), MPa | 970 to 1720 | |
| 810 to 910 |
| Tensile Strength: Yield (Proof), MPa | 510 to 1090 | |
| 660 to 770 |
Thermal Properties
| Latent Heat of Fusion, J/g | 310 | |
| 250 |
| Melting Completion (Liquidus), °C | 1400 | |
| 1460 |
| Melting Onset (Solidus), °C | 1440 | |
| 1420 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 470 |
| Thermal Conductivity, W/m-K | 13 | |
| 46 |
| Thermal Expansion, µm/m-K | 13 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 2.0 | |
| 8.0 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 2.1 | |
| 9.1 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 95 | |
| 5.0 |
| Density, g/cm3 | 8.4 | |
| 7.9 |
| Embodied Carbon, kg CO2/kg material | 8.0 | |
| 2.0 |
| Embodied Energy, MJ/kg | 110 | |
| 27 |
| Embodied Water, L/kg | 400 | |
| 61 |
Common Calculations
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 600 to 2790 | |
| 1140 to 1580 |
| Stiffness to Weight: Axial, points | 14 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 32 to 57 | |
| 29 to 32 |
| Strength to Weight: Bending, points | 26 to 38 | |
| 24 to 27 |
| Thermal Diffusivity, mm2/s | 3.3 | |
| 12 |
| Thermal Shock Resistance, points | 26 to 45 | |
| 24 to 27 |
Alloy Composition
| Boron (B), % | 0 to 0.1 | |
| 0 |
| Carbon (C), % | 0 to 0.15 | |
| 0 to 0.23 |
| Chromium (Cr), % | 19 to 21 | |
| 1.5 to 2.0 |
| Cobalt (Co), % | 39 to 41 | |
| 0 |
| Iron (Fe), % | 10 to 20.5 | |
| 92.5 to 95.1 |
| Manganese (Mn), % | 1.5 to 2.5 | |
| 0.2 to 0.4 |
| Molybdenum (Mo), % | 6.0 to 8.0 | |
| 0.4 to 0.6 |
| Nickel (Ni), % | 14 to 16 | |
| 2.8 to 3.9 |
| Phosphorus (P), % | 0 to 0.015 | |
| 0 to 0.015 |
| Silicon (Si), % | 0 to 1.2 | |
| 0 to 0.3 |
| Sulfur (S), % | 0 to 0.015 | |
| 0 to 0.010 |
| Vanadium (V), % | 0 | |
| 0 to 0.080 |