R30155 Cobalt vs. Nickel 718
R30155 cobalt belongs to the iron alloys classification, while nickel 718 belongs to the nickel alloys. They have 62% of their average alloy composition in common. There are 29 material properties with values for both materials. Properties with values for just one material (8, in this case) are not shown.
For each property being compared, the top bar is R30155 cobalt and the bottom bar is nickel 718.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 210 | |
| 190 |
| Elongation at Break, % | 34 | |
| 12 to 50 |
| Fatigue Strength, MPa | 310 | |
| 460 to 760 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Reduction in Area, % | 34 | |
| 34 to 64 |
| Shear Modulus, GPa | 81 | |
| 75 |
| Shear Strength, MPa | 570 | |
| 660 to 950 |
| Tensile Strength: Ultimate (UTS), MPa | 850 | |
| 930 to 1530 |
| Tensile Strength: Yield (Proof), MPa | 390 | |
| 510 to 1330 |
Thermal Properties
| Latent Heat of Fusion, J/g | 300 | |
| 310 |
| Maximum Temperature: Mechanical, °C | 1100 | |
| 980 |
| Melting Completion (Liquidus), °C | 1470 | |
| 1340 |
| Melting Onset (Solidus), °C | 1420 | |
| 1260 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 450 |
| Thermal Conductivity, W/m-K | 12 | |
| 11 |
| Thermal Expansion, µm/m-K | 14 | |
| 13 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 80 | |
| 75 |
| Density, g/cm3 | 8.5 | |
| 8.3 |
| Embodied Carbon, kg CO2/kg material | 9.7 | |
| 13 |
| Embodied Energy, MJ/kg | 150 | |
| 190 |
| Embodied Water, L/kg | 300 | |
| 250 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 230 | |
| 140 to 390 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 370 | |
| 660 to 4560 |
| Stiffness to Weight: Axial, points | 14 | |
| 13 |
| Stiffness to Weight: Bending, points | 23 | |
| 23 |
| Strength to Weight: Axial, points | 28 | |
| 31 to 51 |
| Strength to Weight: Bending, points | 24 | |
| 25 to 35 |
| Thermal Diffusivity, mm2/s | 3.2 | |
| 3.0 |
| Thermal Shock Resistance, points | 21 | |
| 27 to 44 |
Alloy Composition
| Aluminum (Al), % | 0 | |
| 0.2 to 0.8 |
| Boron (B), % | 0 | |
| 0 to 0.0060 |
| Carbon (C), % | 0.080 to 0.16 | |
| 0 to 0.080 |
| Chromium (Cr), % | 20 to 22.5 | |
| 17 to 21 |
| Cobalt (Co), % | 18.5 to 21 | |
| 0 to 1.0 |
| Copper (Cu), % | 0 | |
| 0 to 0.3 |
| Iron (Fe), % | 24.3 to 36.2 | |
| 11.1 to 24.6 |
| Manganese (Mn), % | 1.0 to 2.0 | |
| 0 to 0.35 |
| Molybdenum (Mo), % | 2.5 to 3.5 | |
| 2.8 to 3.3 |
| Nickel (Ni), % | 19 to 21 | |
| 50 to 55 |
| Niobium (Nb), % | 0.75 to 1.3 | |
| 4.8 to 5.5 |
| Nitrogen (N), % | 0 to 0.2 | |
| 0 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.015 |
| Silicon (Si), % | 0 to 1.0 | |
| 0 to 0.35 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.015 |
| Tantalum (Ta), % | 0.75 to 1.3 | |
| 0 |
| Titanium (Ti), % | 0 | |
| 0.65 to 1.2 |
| Tungsten (W), % | 2.0 to 3.0 | |
| 0 |