Annealed SAE-AISI A9 vs. Annealed R30008 Cobalt
Annealed SAE-AISI A9 belongs to the iron alloys classification, while annealed R30008 cobalt belongs to the cobalt alloys. They have a modest 23% of their average alloy composition in common, which, by itself, doesn't mean much. There are 23 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 annealed SAE-AISI A9 and the bottom bar is annealed R30008 cobalt.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 210 |
| Elongation at Break, % | 21 | |
| 73 |
| Fatigue Strength, MPa | 250 | |
| 320 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 74 | |
| 83 |
| Tensile Strength: Ultimate (UTS), MPa | 770 | |
| 950 |
| Tensile Strength: Yield (Proof), MPa | 360 | |
| 500 |
Thermal Properties
| Latent Heat of Fusion, J/g | 280 | |
| 320 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1400 |
| Melting Onset (Solidus), °C | 1410 | |
| 1330 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 450 |
| Thermal Expansion, µm/m-K | 12 | |
| 13 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 7.0 | |
| 95 |
| Density, g/cm3 | 7.8 | |
| 8.4 |
| Embodied Carbon, kg CO2/kg material | 4.7 | |
| 8.1 |
| Embodied Energy, MJ/kg | 70 | |
| 110 |
| Embodied Water, L/kg | 82 | |
| 400 |
Common Calculations
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 350 | |
| 590 |
| Stiffness to Weight: Axial, points | 14 | |
| 14 |
| Stiffness to Weight: Bending, points | 25 | |
| 24 |
| Strength to Weight: Axial, points | 28 | |
| 31 |
| Strength to Weight: Bending, points | 24 | |
| 25 |
| Thermal Shock Resistance, points | 25 | |
| 25 |
Alloy Composition
| Boron (B), % | 0 | |
| 0 to 0.0010 |
| Carbon (C), % | 0.45 to 0.55 | |
| 0 to 0.15 |
| Chromium (Cr), % | 4.8 to 5.5 | |
| 18.5 to 21.5 |
| Cobalt (Co), % | 0 | |
| 39 to 42 |
| Copper (Cu), % | 0 to 0.25 | |
| 0 |
| Iron (Fe), % | 87 to 90.5 | |
| 7.6 to 20 |
| Manganese (Mn), % | 0 to 0.5 | |
| 1.0 to 2.0 |
| Molybdenum (Mo), % | 1.3 to 1.8 | |
| 6.5 to 7.5 |
| Nickel (Ni), % | 1.3 to 1.8 | |
| 15 to 18 |
| Phosphorus (P), % | 0 to 0.030 | |
| 0 to 0.015 |
| Silicon (Si), % | 1.0 to 1.2 | |
| 0 to 1.2 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.015 |
| Vanadium (V), % | 0.8 to 1.4 | |
| 0 |