R30008 Cobalt vs. ASTM B685 Alloy
R30008 cobalt belongs to the cobalt alloys classification, while ASTM B685 alloy belongs to the otherwise unclassified metals. There are 15 material properties with values for both materials. Properties with values for just one material (10, in this case) are not shown.
For each property being compared, the top bar is R30008 cobalt and the bottom bar is ASTM B685 alloy.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 210 | |
| 120 |
| Poisson's Ratio | 0.29 | |
| 0.37 |
| Shear Modulus, GPa | 83 | |
| 43 |
| Tensile Strength: Ultimate (UTS), MPa | 950 to 1700 | |
| 660 to 1060 |
Thermal Properties
| Latent Heat of Fusion, J/g | 320 | |
| 180 |
| Melting Completion (Liquidus), °C | 1400 | |
| 1230 |
| Melting Onset (Solidus), °C | 1330 | |
| 1200 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 300 |
| Thermal Expansion, µm/m-K | 13 | |
| 14 |
Otherwise Unclassified Properties
| Density, g/cm3 | 8.4 | |
| 11 |
Common Calculations
| Stiffness to Weight: Axial, points | 14 | |
| 6.1 |
| Stiffness to Weight: Bending, points | 24 | |
| 15 |
| Strength to Weight: Axial, points | 31 to 56 | |
| 17 to 27 |
| Strength to Weight: Bending, points | 25 to 37 | |
| 16 to 21 |
| Thermal Shock Resistance, points | 25 to 44 | |
| 28 to 46 |
Alloy Composition
| Aluminum (Al), % | 0 | |
| 0 to 0.0050 |
| Boron (B), % | 0 to 0.0010 | |
| 0 |
| Cadmium (Cd), % | 0 | |
| 0 to 0.050 |
| Carbon (C), % | 0 to 0.15 | |
| 0 |
| Chromium (Cr), % | 18.5 to 21.5 | |
| 0 |
| Cobalt (Co), % | 39 to 42 | |
| 0 |
| Copper (Cu), % | 0 | |
| 39.5 to 40.5 |
| Iron (Fe), % | 7.6 to 20 | |
| 0 to 0.050 |
| Lead (Pb), % | 0 | |
| 0 to 0.030 |
| Manganese (Mn), % | 1.0 to 2.0 | |
| 0 |
| Molybdenum (Mo), % | 6.5 to 7.5 | |
| 0 |
| Nickel (Ni), % | 15 to 18 | |
| 0 |
| Palladium (Pd), % | 0 | |
| 59 to 60.5 |
| Phosphorus (P), % | 0 to 0.015 | |
| 0 |
| Silicon (Si), % | 0 to 1.2 | |
| 0 |
| Silver (Ag), % | 0 | |
| 0 to 0.1 |
| Sulfur (S), % | 0 to 0.015 | |
| 0 |
| Zinc (Zn), % | 0 | |
| 0 to 0.060 |
| Residuals, % | 0 | |
| 0 to 0.2 |