AISI 440A Stainless Steel vs. Nickel 684
AISI 440A stainless steel belongs to the iron alloys classification, while nickel 684 belongs to the nickel alloys. They have a modest 20% of their average alloy composition in common, which, by itself, doesn't mean much. There are 25 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 440A stainless steel and the bottom bar is nickel 684.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 200 | |
| 200 |
| Elongation at Break, % | 5.0 to 20 | |
| 11 |
| Fatigue Strength, MPa | 270 to 790 | |
| 390 |
| Poisson's Ratio | 0.28 | |
| 0.29 |
| Shear Modulus, GPa | 77 | |
| 76 |
| Shear Strength, MPa | 450 to 1040 | |
| 710 |
| Tensile Strength: Ultimate (UTS), MPa | 730 to 1790 | |
| 1190 |
| Tensile Strength: Yield (Proof), MPa | 420 to 1650 | |
| 800 |
Thermal Properties
| Latent Heat of Fusion, J/g | 280 | |
| 320 |
| Maximum Temperature: Mechanical, °C | 760 | |
| 1000 |
| Melting Completion (Liquidus), °C | 1480 | |
| 1370 |
| Melting Onset (Solidus), °C | 1370 | |
| 1320 |
| Specific Heat Capacity, J/kg-K | 480 | |
| 470 |
| Thermal Expansion, µm/m-K | 10 | |
| 13 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 9.0 | |
| 75 |
| Density, g/cm3 | 7.7 | |
| 8.3 |
| Embodied Carbon, kg CO2/kg material | 2.2 | |
| 10 |
| Embodied Energy, MJ/kg | 31 | |
| 140 |
| Embodied Water, L/kg | 120 | |
| 360 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 87 to 120 | |
| 120 |
| Stiffness to Weight: Axial, points | 14 | |
| 13 |
| Stiffness to Weight: Bending, points | 25 | |
| 23 |
| Strength to Weight: Axial, points | 26 to 65 | |
| 40 |
| Strength to Weight: Bending, points | 23 to 43 | |
| 30 |
| Thermal Shock Resistance, points | 26 to 65 | |
| 34 |
Alloy Composition
| Aluminum (Al), % | 0 | |
| 2.5 to 3.3 |
| Boron (B), % | 0 | |
| 0.0030 to 0.010 |
| Carbon (C), % | 0.6 to 0.75 | |
| 0 to 0.15 |
| Chromium (Cr), % | 16 to 18 | |
| 15 to 20 |
| Cobalt (Co), % | 0 | |
| 13 to 20 |
| Copper (Cu), % | 0 | |
| 0 to 0.15 |
| Iron (Fe), % | 78.4 to 83.4 | |
| 0 to 4.0 |
| Manganese (Mn), % | 0 to 1.0 | |
| 0 to 0.75 |
| Molybdenum (Mo), % | 0 to 0.75 | |
| 3.0 to 5.0 |
| Nickel (Ni), % | 0 | |
| 42.7 to 64 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.015 |
| Silicon (Si), % | 0 to 1.0 | |
| 0 to 0.75 |
| Sulfur (S), % | 0 to 0.015 | |
| 0 to 0.015 |
| Titanium (Ti), % | 0 | |
| 2.5 to 3.3 |