SAE-AISI 4620 Steel vs. R30155 Cobalt
Both SAE-AISI 4620 steel and R30155 cobalt are iron alloys. They have a modest 33% of their average alloy composition in common, which, by itself, doesn't mean much. There are 29 material properties with values for both materials. Properties with values for just one material (5, in this case) are not shown.
For each property being compared, the top bar is SAE-AISI 4620 steel and the bottom bar is R30155 cobalt.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 150 to 210 | |
| 220 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 210 |
| Elongation at Break, % | 16 to 27 | |
| 34 |
| Fatigue Strength, MPa | 260 to 360 | |
| 310 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 73 | |
| 81 |
| Shear Strength, MPa | 320 to 420 | |
| 570 |
| Tensile Strength: Ultimate (UTS), MPa | 490 to 680 | |
| 850 |
| Tensile Strength: Yield (Proof), MPa | 350 to 550 | |
| 390 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 300 |
| Maximum Temperature: Mechanical, °C | 410 | |
| 1100 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1470 |
| Melting Onset (Solidus), °C | 1420 | |
| 1420 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 450 |
| Thermal Conductivity, W/m-K | 47 | |
| 12 |
| Thermal Expansion, µm/m-K | 13 | |
| 14 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 3.2 | |
| 80 |
| Density, g/cm3 | 7.9 | |
| 8.5 |
| Embodied Carbon, kg CO2/kg material | 1.6 | |
| 9.7 |
| Embodied Energy, MJ/kg | 22 | |
| 150 |
| Embodied Water, L/kg | 50 | |
| 300 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 100 to 120 | |
| 230 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 330 to 800 | |
| 370 |
| Stiffness to Weight: Axial, points | 13 | |
| 14 |
| Stiffness to Weight: Bending, points | 24 | |
| 23 |
| Strength to Weight: Axial, points | 17 to 24 | |
| 28 |
| Strength to Weight: Bending, points | 18 to 22 | |
| 24 |
| Thermal Diffusivity, mm2/s | 13 | |
| 3.2 |
| Thermal Shock Resistance, points | 15 to 20 | |
| 21 |
Alloy Composition
| Carbon (C), % | 0.17 to 0.22 | |
| 0.080 to 0.16 |
| Chromium (Cr), % | 0 | |
| 20 to 22.5 |
| Cobalt (Co), % | 0 | |
| 18.5 to 21 |
| Iron (Fe), % | 96.4 to 97.4 | |
| 24.3 to 36.2 |
| Manganese (Mn), % | 0.45 to 0.65 | |
| 1.0 to 2.0 |
| Molybdenum (Mo), % | 0.2 to 0.3 | |
| 2.5 to 3.5 |
| Nickel (Ni), % | 1.7 to 2.0 | |
| 19 to 21 |
| Niobium (Nb), % | 0 | |
| 0.75 to 1.3 |
| Nitrogen (N), % | 0 | |
| 0 to 0.2 |
| Phosphorus (P), % | 0 to 0.035 | |
| 0 to 0.040 |
| Silicon (Si), % | 0.15 to 0.35 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 to 0.040 | |
| 0 to 0.030 |
| Tantalum (Ta), % | 0 | |
| 0.75 to 1.3 |
| Tungsten (W), % | 0 | |
| 2.0 to 3.0 |