Nickel 718 vs. AISI 440A Stainless Steel
Nickel 718 belongs to the nickel alloys classification, while AISI 440A stainless steel belongs to the iron alloys. They have a modest 36% 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 (7, in this case) are not shown.
For each property being compared, the top bar is nickel 718 and the bottom bar is AISI 440A stainless steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 200 |
| Elongation at Break, % | 12 to 50 | |
| 5.0 to 20 |
| Fatigue Strength, MPa | 460 to 760 | |
| 270 to 790 |
| Poisson's Ratio | 0.29 | |
| 0.28 |
| Shear Modulus, GPa | 75 | |
| 77 |
| Shear Strength, MPa | 660 to 950 | |
| 450 to 1040 |
| Tensile Strength: Ultimate (UTS), MPa | 930 to 1530 | |
| 730 to 1790 |
| Tensile Strength: Yield (Proof), MPa | 510 to 1330 | |
| 420 to 1650 |
Thermal Properties
| Latent Heat of Fusion, J/g | 310 | |
| 280 |
| Maximum Temperature: Mechanical, °C | 980 | |
| 760 |
| Melting Completion (Liquidus), °C | 1340 | |
| 1480 |
| Melting Onset (Solidus), °C | 1260 | |
| 1370 |
| Specific Heat Capacity, J/kg-K | 450 | |
| 480 |
| Thermal Conductivity, W/m-K | 11 | |
| 23 |
| Thermal Expansion, µm/m-K | 13 | |
| 10 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 1.4 | |
| 2.5 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 1.5 | |
| 2.9 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 75 | |
| 9.0 |
| Density, g/cm3 | 8.3 | |
| 7.7 |
| Embodied Carbon, kg CO2/kg material | 13 | |
| 2.2 |
| Embodied Energy, MJ/kg | 190 | |
| 31 |
| Embodied Water, L/kg | 250 | |
| 120 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 140 to 390 | |
| 87 to 120 |
| Stiffness to Weight: Axial, points | 13 | |
| 14 |
| Stiffness to Weight: Bending, points | 23 | |
| 25 |
| Strength to Weight: Axial, points | 31 to 51 | |
| 26 to 65 |
| Strength to Weight: Bending, points | 25 to 35 | |
| 23 to 43 |
| Thermal Diffusivity, mm2/s | 3.0 | |
| 6.2 |
| Thermal Shock Resistance, points | 27 to 44 | |
| 26 to 65 |
Alloy Composition
| Aluminum (Al), % | 0.2 to 0.8 | |
| 0 |
| Boron (B), % | 0 to 0.0060 | |
| 0 |
| Carbon (C), % | 0 to 0.080 | |
| 0.6 to 0.75 |
| Chromium (Cr), % | 17 to 21 | |
| 16 to 18 |
| Cobalt (Co), % | 0 to 1.0 | |
| 0 |
| Copper (Cu), % | 0 to 0.3 | |
| 0 |
| Iron (Fe), % | 11.1 to 24.6 | |
| 78.4 to 83.4 |
| Manganese (Mn), % | 0 to 0.35 | |
| 0 to 1.0 |
| Molybdenum (Mo), % | 2.8 to 3.3 | |
| 0 to 0.75 |
| Nickel (Ni), % | 50 to 55 | |
| 0 |
| Niobium (Nb), % | 4.8 to 5.5 | |
| 0 |
| Phosphorus (P), % | 0 to 0.015 | |
| 0 to 0.040 |
| Silicon (Si), % | 0 to 0.35 | |
| 0 to 1.0 |
| Sulfur (S), % | 0 to 0.015 | |
| 0 to 0.015 |
| Titanium (Ti), % | 0.65 to 1.2 | |
| 0 |