ACI-ASTM CB7Cu-2 Steel vs. R30035 Cobalt
ACI-ASTM CB7Cu-2 steel belongs to the iron alloys classification, while R30035 cobalt belongs to the cobalt alloys. They have a modest 20% of their average alloy composition in common, which, by itself, doesn't mean much. There are 28 material properties with values for both materials. Properties with values for just one material (3, in this case) are not shown.
For each property being compared, the top bar is ACI-ASTM CB7Cu-2 steel and the bottom bar is R30035 cobalt.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 220 to 230 |
| Elongation at Break, % | 5.7 to 11 | |
| 9.0 to 46 |
| Fatigue Strength, MPa | 420 to 590 | |
| 170 to 740 |
| Poisson's Ratio | 0.28 | |
| 0.29 |
| Shear Modulus, GPa | 75 | |
| 84 to 89 |
| Tensile Strength: Ultimate (UTS), MPa | 960 to 1350 | |
| 900 to 1900 |
| Tensile Strength: Yield (Proof), MPa | 760 to 1180 | |
| 300 to 1650 |
Thermal Properties
| Latent Heat of Fusion, J/g | 280 | |
| 320 |
| Melting Completion (Liquidus), °C | 1430 | |
| 1440 |
| Melting Onset (Solidus), °C | 1380 | |
| 1320 |
| Specific Heat Capacity, J/kg-K | 480 | |
| 440 |
| Thermal Conductivity, W/m-K | 17 | |
| 11 |
| Thermal Expansion, µm/m-K | 11 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 2.1 | |
| 1.7 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 2.4 | |
| 1.8 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 13 | |
| 100 |
| Density, g/cm3 | 7.8 | |
| 8.7 |
| Embodied Carbon, kg CO2/kg material | 2.6 | |
| 10 |
| Embodied Energy, MJ/kg | 38 | |
| 140 |
| Embodied Water, L/kg | 130 | |
| 410 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 71 to 120 | |
| 160 to 320 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 1510 to 3600 | |
| 210 to 5920 |
| Stiffness to Weight: Axial, points | 14 | |
| 14 to 15 |
| Stiffness to Weight: Bending, points | 25 | |
| 23 to 24 |
| Strength to Weight: Axial, points | 34 to 48 | |
| 29 to 61 |
| Strength to Weight: Bending, points | 28 to 35 | |
| 24 to 39 |
| Thermal Diffusivity, mm2/s | 4.6 | |
| 3.0 |
| Thermal Shock Resistance, points | 32 to 45 | |
| 23 to 46 |
Alloy Composition
| Boron (B), % | 0 | |
| 0 to 0.015 |
| Carbon (C), % | 0 to 0.070 | |
| 0 to 0.025 |
| Chromium (Cr), % | 14 to 15.5 | |
| 19 to 21 |
| Cobalt (Co), % | 0 | |
| 29.1 to 39 |
| Copper (Cu), % | 2.5 to 3.2 | |
| 0 |
| Iron (Fe), % | 73.6 to 79 | |
| 0 to 1.0 |
| Manganese (Mn), % | 0 to 0.7 | |
| 0 to 0.15 |
| Molybdenum (Mo), % | 0 | |
| 9.0 to 10.5 |
| Nickel (Ni), % | 4.5 to 5.5 | |
| 33 to 37 |
| Niobium (Nb), % | 0 to 0.35 | |
| 0 |
| Nitrogen (N), % | 0 to 0.050 | |
| 0 |
| Phosphorus (P), % | 0 to 0.035 | |
| 0 to 0.015 |
| Silicon (Si), % | 0 to 1.0 | |
| 0 to 0.15 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.010 |
| Titanium (Ti), % | 0 | |
| 0 to 1.0 |