Annealed R31538 Cobalt vs. Annealed SAE-AISI M44
Annealed R31538 cobalt belongs to the cobalt alloys classification, while annealed SAE-AISI M44 belongs to the iron alloys. They have a modest 24% of their average alloy composition in common, which, by itself, doesn't mean much. There are 20 material properties with values for both materials. Properties with values for just one material (12, in this case) are not shown.
For each property being compared, the top bar is annealed R31538 cobalt and the bottom bar is annealed SAE-AISI M44.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 220 | |
| 200 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 86 | |
| 78 |
| Tensile Strength: Ultimate (UTS), MPa | 1020 | |
| 870 |
Thermal Properties
| Latent Heat of Fusion, J/g | 320 | |
| 270 |
| Melting Completion (Liquidus), °C | 1360 | |
| 1590 |
| Melting Onset (Solidus), °C | 1290 | |
| 1540 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 440 |
| Thermal Conductivity, W/m-K | 13 | |
| 14 |
| Thermal Expansion, µm/m-K | 13 | |
| 12 |
Otherwise Unclassified Properties
| Density, g/cm3 | 8.4 | |
| 8.4 |
| Embodied Carbon, kg CO2/kg material | 8.1 | |
| 9.9 |
| Embodied Energy, MJ/kg | 110 | |
| 150 |
| Embodied Water, L/kg | 530 | |
| 170 |
Common Calculations
| Stiffness to Weight: Axial, points | 15 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 23 |
| Strength to Weight: Axial, points | 34 | |
| 28 |
| Strength to Weight: Bending, points | 27 | |
| 24 |
| Thermal Diffusivity, mm2/s | 3.5 | |
| 3.7 |
| Thermal Shock Resistance, points | 25 | |
| 27 |
Alloy Composition
| Carbon (C), % | 0.15 to 0.35 | |
| 1.1 to 1.2 |
| Chromium (Cr), % | 26 to 30 | |
| 4.0 to 4.8 |
| Cobalt (Co), % | 58.7 to 68.9 | |
| 11 to 12.3 |
| Copper (Cu), % | 0 | |
| 0 to 0.25 |
| Iron (Fe), % | 0 to 0.75 | |
| 65.3 to 70.6 |
| Manganese (Mn), % | 0 to 1.0 | |
| 0.2 to 0.4 |
| Molybdenum (Mo), % | 5.0 to 7.0 | |
| 6.0 to 7.0 |
| Nickel (Ni), % | 0 to 1.0 | |
| 0 to 0.3 |
| Nitrogen (N), % | 0 to 0.25 | |
| 0 |
| Phosphorus (P), % | 0 | |
| 0 to 0.030 |
| Silicon (Si), % | 0 to 1.0 | |
| 0.3 to 0.55 |
| Sulfur (S), % | 0 | |
| 0 to 0.030 |
| Tungsten (W), % | 0 | |
| 5.0 to 5.8 |
| Vanadium (V), % | 0 | |
| 1.9 to 2.2 |