Nickel 718 vs. SAE-AISI H21 Steel
Nickel 718 belongs to the nickel alloys classification, while SAE-AISI H21 steel belongs to the iron alloys. They have a modest 22% of their average alloy composition in common, which, by itself, doesn't mean much. There are 21 material properties with values for both materials. Properties with values for just one material (14, in this case) are not shown.
For each property being compared, the top bar is nickel 718 and the bottom bar is SAE-AISI H21 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 200 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 75 | |
| 76 |
| Tensile Strength: Ultimate (UTS), MPa | 930 to 1530 | |
| 720 to 1790 |
Thermal Properties
| Latent Heat of Fusion, J/g | 310 | |
| 250 |
| Melting Completion (Liquidus), °C | 1340 | |
| 1630 |
| Melting Onset (Solidus), °C | 1260 | |
| 1580 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 440 |
| Thermal Conductivity, W/m-K | 11 | |
| 27 |
| Thermal Expansion, µm/m-K | 13 | |
| 11 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 75 | |
| 23 |
| Density, g/cm3 | 8.3 | |
| 8.5 |
| Embodied Carbon, kg CO2/kg material | 13 | |
| 4.5 |
| Embodied Energy, MJ/kg | 190 | |
| 68 |
| Embodied Water, L/kg | 250 | |
| 72 |
Common Calculations
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 23 | |
| 23 |
| Strength to Weight: Axial, points | 31 to 51 | |
| 23 to 58 |
| Strength to Weight: Bending, points | 25 to 35 | |
| 21 to 38 |
| Thermal Diffusivity, mm2/s | 3.0 | |
| 7.1 |
| Thermal Shock Resistance, points | 27 to 44 | |
| 24 to 59 |
Alloy Composition
| Aluminum (Al), % | 0.2 to 0.8 | |
| 0 |
| Boron (B), % | 0 to 0.0060 | |
| 0 |
| Carbon (C), % | 0 to 0.080 | |
| 0.28 to 0.36 |
| Chromium (Cr), % | 17 to 21 | |
| 3.0 to 3.8 |
| Cobalt (Co), % | 0 to 1.0 | |
| 0 |
| Copper (Cu), % | 0 to 0.3 | |
| 0 to 0.25 |
| Iron (Fe), % | 11.1 to 24.6 | |
| 87.6 to 93.8 |
| Manganese (Mn), % | 0 to 0.35 | |
| 0.15 to 0.4 |
| Molybdenum (Mo), % | 2.8 to 3.3 | |
| 0 |
| Nickel (Ni), % | 50 to 55 | |
| 0 to 0.3 |
| Niobium (Nb), % | 4.8 to 5.5 | |
| 0 |
| Phosphorus (P), % | 0 to 0.015 | |
| 0 to 0.030 |
| Silicon (Si), % | 0 to 0.35 | |
| 0.15 to 0.5 |
| Sulfur (S), % | 0 to 0.015 | |
| 0 to 0.030 |
| Titanium (Ti), % | 0.65 to 1.2 | |
| 0 |
| Tungsten (W), % | 0 | |
| 8.5 to 10 |
| Vanadium (V), % | 0 | |
| 0.3 to 0.6 |