R30035 Cobalt vs. SAE-AISI 4340 Steel
R30035 cobalt belongs to the cobalt alloys classification, while SAE-AISI 4340 steel belongs to the iron alloys. There are 28 material properties with values for both materials. Properties with values for just one material (4, in this case) are not shown.
For each property being compared, the top bar is R30035 cobalt and the bottom bar is SAE-AISI 4340 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 220 to 230 | |
| 190 |
| Elongation at Break, % | 9.0 to 46 | |
| 12 to 22 |
| Fatigue Strength, MPa | 170 to 740 | |
| 330 to 740 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 84 to 89 | |
| 73 |
| Tensile Strength: Ultimate (UTS), MPa | 900 to 1900 | |
| 690 to 1280 |
| Tensile Strength: Yield (Proof), MPa | 300 to 1650 | |
| 470 to 1150 |
Thermal Properties
| Latent Heat of Fusion, J/g | 320 | |
| 250 |
| Melting Completion (Liquidus), °C | 1440 | |
| 1460 |
| Melting Onset (Solidus), °C | 1320 | |
| 1420 |
| Specific Heat Capacity, J/kg-K | 440 | |
| 470 |
| Thermal Conductivity, W/m-K | 11 | |
| 44 |
| Thermal Expansion, µm/m-K | 13 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 1.7 | |
| 7.5 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 1.8 | |
| 8.6 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 100 | |
| 3.5 |
| Density, g/cm3 | 8.7 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 10 | |
| 1.7 |
| Embodied Energy, MJ/kg | 140 | |
| 22 |
| Embodied Water, L/kg | 410 | |
| 53 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 160 to 320 | |
| 79 to 170 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 210 to 5920 | |
| 590 to 3490 |
| Stiffness to Weight: Axial, points | 14 to 15 | |
| 13 |
| Stiffness to Weight: Bending, points | 23 to 24 | |
| 24 |
| Strength to Weight: Axial, points | 29 to 61 | |
| 24 to 45 |
| Strength to Weight: Bending, points | 24 to 39 | |
| 22 to 33 |
| Thermal Diffusivity, mm2/s | 3.0 | |
| 12 |
| Thermal Shock Resistance, points | 23 to 46 | |
| 20 to 38 |
Alloy Composition
| Boron (B), % | 0 to 0.015 | |
| 0 |
| Carbon (C), % | 0 to 0.025 | |
| 0.38 to 0.43 |
| Chromium (Cr), % | 19 to 21 | |
| 0.7 to 0.9 |
| Cobalt (Co), % | 29.1 to 39 | |
| 0 |
| Iron (Fe), % | 0 to 1.0 | |
| 95.1 to 96.3 |
| Manganese (Mn), % | 0 to 0.15 | |
| 0.6 to 0.8 |
| Molybdenum (Mo), % | 9.0 to 10.5 | |
| 0.2 to 0.3 |
| Nickel (Ni), % | 33 to 37 | |
| 1.7 to 2.0 |
| Phosphorus (P), % | 0 to 0.015 | |
| 0 to 0.035 |
| Silicon (Si), % | 0 to 0.15 | |
| 0.15 to 0.35 |
| Sulfur (S), % | 0 to 0.010 | |
| 0 to 0.040 |
| Titanium (Ti), % | 0 to 1.0 | |
| 0 |