S15700 Stainless Steel vs. R30816 Cobalt
S15700 stainless steel belongs to the iron alloys classification, while R30816 cobalt belongs to the cobalt alloys. They have a modest 28% of their average alloy composition in common, which, by itself, doesn't mean much. There are 26 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 S15700 stainless steel and the bottom bar is R30816 cobalt.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 200 to 460 | |
| 280 |
| Elastic (Young's, Tensile) Modulus, GPa | 200 | |
| 210 |
| Elongation at Break, % | 1.1 to 29 | |
| 23 |
| Fatigue Strength, MPa | 370 to 770 | |
| 250 |
| Poisson's Ratio | 0.28 | |
| 0.3 |
| Shear Modulus, GPa | 77 | |
| 81 |
| Tensile Strength: Ultimate (UTS), MPa | 1180 to 1890 | |
| 1020 |
| Tensile Strength: Yield (Proof), MPa | 500 to 1770 | |
| 460 |
Thermal Properties
| Latent Heat of Fusion, J/g | 290 | |
| 300 |
| Melting Completion (Liquidus), °C | 1440 | |
| 1540 |
| Melting Onset (Solidus), °C | 1400 | |
| 1460 |
| Specific Heat Capacity, J/kg-K | 480 | |
| 420 |
| Thermal Conductivity, W/m-K | 16 | |
| 13 |
| Thermal Expansion, µm/m-K | 11 | |
| 12 |
Otherwise Unclassified Properties
| Density, g/cm3 | 7.8 | |
| 9.1 |
| Embodied Carbon, kg CO2/kg material | 3.4 | |
| 20 |
| Embodied Energy, MJ/kg | 47 | |
| 320 |
| Embodied Water, L/kg | 140 | |
| 440 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 17 to 270 | |
| 190 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 640 to 4660 | |
| 510 |
| Stiffness to Weight: Axial, points | 14 | |
| 13 |
| Stiffness to Weight: Bending, points | 25 | |
| 22 |
| Strength to Weight: Axial, points | 42 to 67 | |
| 31 |
| Strength to Weight: Bending, points | 32 to 43 | |
| 25 |
| Thermal Diffusivity, mm2/s | 4.2 | |
| 3.3 |
| Thermal Shock Resistance, points | 39 to 63 | |
| 28 |
Alloy Composition
| Aluminum (Al), % | 0.75 to 1.5 | |
| 0 |
| Carbon (C), % | 0 to 0.090 | |
| 0.32 to 0.42 |
| Chromium (Cr), % | 14 to 16 | |
| 19 to 21 |
| Cobalt (Co), % | 0 | |
| 40 to 49.8 |
| Iron (Fe), % | 69.6 to 76.8 | |
| 0 to 5.0 |
| Manganese (Mn), % | 0 to 1.0 | |
| 1.0 to 2.0 |
| Molybdenum (Mo), % | 2.0 to 3.0 | |
| 3.5 to 4.5 |
| Nickel (Ni), % | 6.5 to 7.7 | |
| 19 to 21 |
| Niobium (Nb), % | 0 | |
| 3.5 to 4.5 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.040 |
| Silicon (Si), % | 0 to 1.0 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.030 |
| Tantalum (Ta), % | 0 | |
| 3.5 to 4.5 |
| Tungsten (W), % | 0 | |
| 3.5 to 4.5 |