S17400 Stainless Steel vs. R30016 Cobalt
S17400 stainless steel belongs to the iron alloys classification, while R30016 cobalt belongs to the cobalt alloys. They have a modest 20% of their average alloy composition in common, which, by itself, doesn't mean much. There are 30 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 S17400 stainless steel and the bottom bar is R30016 cobalt.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 220 |
| Elongation at Break, % | 11 to 21 | |
| 8.4 |
| Fatigue Strength, MPa | 380 to 670 | |
| 290 |
| Impact Strength: V-Notched Charpy, J | 7.6 to 86 | |
| 8.0 |
| Poisson's Ratio | 0.28 | |
| 0.28 |
| Reduction in Area, % | 40 to 62 | |
| 8.0 |
| Rockwell C Hardness | 27 to 43 | |
| 37 |
| Shear Modulus, GPa | 75 | |
| 85 |
| Tensile Strength: Ultimate (UTS), MPa | 910 to 1390 | |
| 1010 |
| Tensile Strength: Yield (Proof), MPa | 580 to 1250 | |
| 580 |
Thermal Properties
| Latent Heat of Fusion, J/g | 280 | |
| 320 |
| Melting Completion (Liquidus), °C | 1440 | |
| 1360 |
| Melting Onset (Solidus), °C | 1400 | |
| 1270 |
| Specific Heat Capacity, J/kg-K | 480 | |
| 450 |
| Thermal Conductivity, W/m-K | 17 | |
| 15 |
| Thermal Expansion, µm/m-K | 11 | |
| 14 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 2.3 | |
| 1.9 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 2.6 | |
| 2.0 |
Otherwise Unclassified Properties
| Density, g/cm3 | 7.8 | |
| 8.5 |
| Embodied Carbon, kg CO2/kg material | 2.7 | |
| 7.7 |
| Embodied Energy, MJ/kg | 39 | |
| 110 |
| Embodied Water, L/kg | 130 | |
| 500 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 140 to 160 | |
| 72 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 880 to 4060 | |
| 770 |
| Stiffness to Weight: Axial, points | 14 | |
| 14 |
| Stiffness to Weight: Bending, points | 25 | |
| 24 |
| Strength to Weight: Axial, points | 32 to 49 | |
| 33 |
| Strength to Weight: Bending, points | 27 to 35 | |
| 26 |
| Thermal Diffusivity, mm2/s | 4.5 | |
| 3.9 |
| Thermal Shock Resistance, points | 30 to 46 | |
| 24 |
Alloy Composition
| Carbon (C), % | 0 to 0.070 | |
| 0.9 to 1.4 |
| Chromium (Cr), % | 15 to 17 | |
| 28 to 32 |
| Cobalt (Co), % | 0 | |
| 49.6 to 66.9 |
| Copper (Cu), % | 3.0 to 5.0 | |
| 0 |
| Iron (Fe), % | 70.4 to 78.9 | |
| 0 to 3.0 |
| Manganese (Mn), % | 0 to 1.0 | |
| 0.5 to 2.0 |
| Molybdenum (Mo), % | 0 | |
| 0 to 1.5 |
| Nickel (Ni), % | 3.0 to 5.0 | |
| 0 to 3.0 |
| Niobium (Nb), % | 0.15 to 0.45 | |
| 0 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 |
| Silicon (Si), % | 0 to 1.0 | |
| 0.2 to 2.0 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 |
| Tungsten (W), % | 0 | |
| 3.5 to 5.5 |