ASTM A372 Grade J Steel vs. R30816 Cobalt
ASTM A372 grade J 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 (6, in this case) are not shown.
For each property being compared, the top bar is ASTM A372 grade J steel and the bottom bar is R30816 cobalt.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 200 to 310 | |
| 280 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 210 |
| Elongation at Break, % | 17 to 22 | |
| 23 |
| Fatigue Strength, MPa | 310 to 570 | |
| 250 |
| Poisson's Ratio | 0.29 | |
| 0.3 |
| Shear Modulus, GPa | 73 | |
| 81 |
| Tensile Strength: Ultimate (UTS), MPa | 650 to 1020 | |
| 1020 |
| Tensile Strength: Yield (Proof), MPa | 430 to 850 | |
| 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 | 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 | 1.5 | |
| 20 |
| Embodied Energy, MJ/kg | 20 | |
| 320 |
| Embodied Water, L/kg | 51 | |
| 440 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 130 to 170 | |
| 190 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 500 to 1930 | |
| 510 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 22 |
| Strength to Weight: Axial, points | 23 to 36 | |
| 31 |
| Strength to Weight: Bending, points | 21 to 29 | |
| 25 |
| Thermal Diffusivity, mm2/s | 12 | |
| 3.3 |
| Thermal Shock Resistance, points | 19 to 30 | |
| 28 |
Alloy Composition
| Carbon (C), % | 0.35 to 0.5 | |
| 0.32 to 0.42 |
| Chromium (Cr), % | 0.8 to 1.2 | |
| 19 to 21 |
| Cobalt (Co), % | 0 | |
| 40 to 49.8 |
| Iron (Fe), % | 96.7 to 97.8 | |
| 0 to 5.0 |
| Manganese (Mn), % | 0.75 to 1.1 | |
| 1.0 to 2.0 |
| Molybdenum (Mo), % | 0.15 to 0.25 | |
| 3.5 to 4.5 |
| Nickel (Ni), % | 0 | |
| 19 to 21 |
| Niobium (Nb), % | 0 | |
| 3.5 to 4.5 |
| Phosphorus (P), % | 0 to 0.015 | |
| 0 to 0.040 |
| Silicon (Si), % | 0.15 to 0.35 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 to 0.010 | |
| 0 to 0.030 |
| Tantalum (Ta), % | 0 | |
| 3.5 to 4.5 |
| Tungsten (W), % | 0 | |
| 3.5 to 4.5 |