S31727 Stainless Steel vs. R30001 Cobalt
S31727 stainless steel belongs to the iron alloys classification, while R30001 cobalt belongs to the cobalt alloys. They have a modest 22% of their average alloy composition in common, which, by itself, doesn't mean much. There are 19 material properties with values for both materials. Properties with values for just one material (18, in this case) are not shown.
For each property being compared, the top bar is S31727 stainless steel and the bottom bar is R30001 cobalt.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 200 | |
| 220 |
| Elongation at Break, % | 40 | |
| 1.0 |
| Poisson's Ratio | 0.28 | |
| 0.28 |
| Shear Modulus, GPa | 78 | |
| 86 |
| Tensile Strength: Ultimate (UTS), MPa | 630 | |
| 620 |
Thermal Properties
| Latent Heat of Fusion, J/g | 290 | |
| 310 |
| Melting Completion (Liquidus), °C | 1440 | |
| 1530 |
| Melting Onset (Solidus), °C | 1390 | |
| 1260 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 430 |
| Thermal Expansion, µm/m-K | 16 | |
| 11 |
Otherwise Unclassified Properties
| Density, g/cm3 | 8.0 | |
| 9.0 |
| Embodied Carbon, kg CO2/kg material | 4.7 | |
| 8.9 |
| Embodied Energy, MJ/kg | 64 | |
| 130 |
| Embodied Water, L/kg | 180 | |
| 460 |
Common Calculations
| Stiffness to Weight: Axial, points | 14 | |
| 14 |
| Stiffness to Weight: Bending, points | 24 | |
| 22 |
| Strength to Weight: Axial, points | 22 | |
| 19 |
| Strength to Weight: Bending, points | 20 | |
| 18 |
| Thermal Shock Resistance, points | 14 | |
| 19 |
Alloy Composition
| Carbon (C), % | 0 to 0.030 | |
| 2.0 to 3.0 |
| Chromium (Cr), % | 17.5 to 19 | |
| 28 to 32 |
| Cobalt (Co), % | 0 | |
| 43 to 59 |
| Copper (Cu), % | 2.8 to 4.0 | |
| 0 |
| Iron (Fe), % | 53.7 to 61.3 | |
| 0 to 3.0 |
| Manganese (Mn), % | 0 to 1.0 | |
| 0 |
| Molybdenum (Mo), % | 3.8 to 4.5 | |
| 0 to 1.0 |
| Nickel (Ni), % | 14.5 to 16.5 | |
| 0 to 3.0 |
| Nitrogen (N), % | 0.15 to 0.21 | |
| 0 |
| Phosphorus (P), % | 0 to 0.030 | |
| 0 |
| Silicon (Si), % | 0 to 1.0 | |
| 0 to 2.0 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 |
| Tungsten (W), % | 0 | |
| 11 to 13 |