AISI 303 Stainless Steel vs. R30816 Cobalt
AISI 303 stainless steel belongs to the iron alloys classification, while R30816 cobalt belongs to the cobalt alloys. They have a modest 31% 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 (9, in this case) are not shown.
For each property being compared, the top bar is AISI 303 stainless steel and the bottom bar is R30816 cobalt.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 170 to 210 | |
| 280 |
| Elastic (Young's, Tensile) Modulus, GPa | 200 | |
| 210 |
| Elongation at Break, % | 40 to 51 | |
| 23 |
| Fatigue Strength, MPa | 230 to 360 | |
| 250 |
| Poisson's Ratio | 0.28 | |
| 0.3 |
| Shear Modulus, GPa | 77 | |
| 81 |
| Tensile Strength: Ultimate (UTS), MPa | 600 to 690 | |
| 1020 |
| Tensile Strength: Yield (Proof), MPa | 230 to 420 | |
| 460 |
Thermal Properties
| Latent Heat of Fusion, J/g | 290 | |
| 300 |
| Melting Completion (Liquidus), °C | 1450 | |
| 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 | 17 | |
| 12 |
Otherwise Unclassified Properties
| Density, g/cm3 | 7.8 | |
| 9.1 |
| Embodied Carbon, kg CO2/kg material | 3.0 | |
| 20 |
| Embodied Energy, MJ/kg | 42 | |
| 320 |
| Embodied Water, L/kg | 140 | |
| 440 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 240 | |
| 190 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 140 to 440 | |
| 510 |
| Stiffness to Weight: Axial, points | 14 | |
| 13 |
| Stiffness to Weight: Bending, points | 25 | |
| 22 |
| Strength to Weight: Axial, points | 21 to 25 | |
| 31 |
| Strength to Weight: Bending, points | 20 to 22 | |
| 25 |
| Thermal Diffusivity, mm2/s | 4.4 | |
| 3.3 |
| Thermal Shock Resistance, points | 13 to 15 | |
| 28 |
Alloy Composition
| Carbon (C), % | 0 to 0.15 | |
| 0.32 to 0.42 |
| Chromium (Cr), % | 17 to 19 | |
| 19 to 21 |
| Cobalt (Co), % | 0 | |
| 40 to 49.8 |
| Iron (Fe), % | 67.3 to 74.9 | |
| 0 to 5.0 |
| Manganese (Mn), % | 0 to 2.0 | |
| 1.0 to 2.0 |
| Molybdenum (Mo), % | 0 | |
| 3.5 to 4.5 |
| Nickel (Ni), % | 8.0 to 10 | |
| 19 to 21 |
| Niobium (Nb), % | 0 | |
| 3.5 to 4.5 |
| Phosphorus (P), % | 0 to 0.2 | |
| 0 to 0.040 |
| Silicon (Si), % | 0 to 1.0 | |
| 0 to 1.0 |
| Sulfur (S), % | 0.15 to 0.35 | |
| 0 to 0.030 |
| Tantalum (Ta), % | 0 | |
| 3.5 to 4.5 |
| Tungsten (W), % | 0 | |
| 3.5 to 4.5 |