SAE-AISI 8630 Steel vs. R31233 Cobalt
SAE-AISI 8630 steel belongs to the iron alloys classification, while R31233 cobalt belongs to the cobalt alloys. There are 27 material properties with values for both materials. Properties with values for just one material (4, in this case) are not shown.
For each property being compared, the top bar is SAE-AISI 8630 steel and the bottom bar is R31233 cobalt.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 220 |
| Elongation at Break, % | 12 to 24 | |
| 17 |
| Fatigue Strength, MPa | 260 to 350 | |
| 220 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 73 | |
| 85 |
| Tensile Strength: Ultimate (UTS), MPa | 540 to 680 | |
| 1020 |
| Tensile Strength: Yield (Proof), MPa | 360 to 560 | |
| 420 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 320 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1350 |
| Melting Onset (Solidus), °C | 1420 | |
| 1330 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 440 |
| Thermal Conductivity, W/m-K | 39 | |
| 12 |
| Thermal Expansion, µm/m-K | 11 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.3 | |
| 2.0 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.3 | |
| 2.1 |
Otherwise Unclassified Properties
| Density, g/cm3 | 7.8 | |
| 8.6 |
| Embodied Carbon, kg CO2/kg material | 1.5 | |
| 8.4 |
| Embodied Energy, MJ/kg | 20 | |
| 110 |
| Embodied Water, L/kg | 50 | |
| 480 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 78 to 110 | |
| 140 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 340 to 840 | |
| 410 |
| Stiffness to Weight: Axial, points | 13 | |
| 14 |
| Stiffness to Weight: Bending, points | 24 | |
| 23 |
| Strength to Weight: Axial, points | 19 to 24 | |
| 33 |
| Strength to Weight: Bending, points | 19 to 22 | |
| 26 |
| Thermal Diffusivity, mm2/s | 10 | |
| 3.2 |
| Thermal Shock Resistance, points | 18 to 23 | |
| 25 |
Alloy Composition
| Boron (B), % | 0 | |
| 0 to 0.015 |
| Carbon (C), % | 0.28 to 0.33 | |
| 0.020 to 0.1 |
| Chromium (Cr), % | 0.4 to 0.6 | |
| 23.5 to 27.5 |
| Cobalt (Co), % | 0 | |
| 44.7 to 63.3 |
| Iron (Fe), % | 96.8 to 97.9 | |
| 1.0 to 5.0 |
| Manganese (Mn), % | 0.7 to 0.9 | |
| 0.1 to 1.5 |
| Molybdenum (Mo), % | 0.15 to 0.25 | |
| 4.0 to 6.0 |
| Nickel (Ni), % | 0.4 to 0.7 | |
| 7.0 to 11 |
| Nitrogen (N), % | 0 | |
| 0.030 to 0.12 |
| Phosphorus (P), % | 0 to 0.035 | |
| 0 to 0.030 |
| Silicon (Si), % | 0.15 to 0.35 | |
| 0.050 to 1.0 |
| Sulfur (S), % | 0 to 0.040 | |
| 0 to 0.020 |
| Tungsten (W), % | 0 | |
| 1.0 to 3.0 |