S21640 Stainless Steel vs. Nickel 725
S21640 stainless steel belongs to the iron alloys classification, while nickel 725 belongs to the nickel alloys. They have a modest 35% of their average alloy composition in common, which, by itself, doesn't mean much. There are 28 material properties with values for both materials. Properties with values for just one material (6, in this case) are not shown.
For each property being compared, the top bar is S21640 stainless steel and the bottom bar is nickel 725.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 200 | |
| 200 |
| Elongation at Break, % | 46 | |
| 34 |
| Fatigue Strength, MPa | 320 | |
| 260 |
| Poisson's Ratio | 0.28 | |
| 0.29 |
| Shear Modulus, GPa | 78 | |
| 78 |
| Shear Strength, MPa | 520 | |
| 580 |
| Tensile Strength: Ultimate (UTS), MPa | 740 | |
| 860 |
| Tensile Strength: Yield (Proof), MPa | 350 | |
| 350 |
Thermal Properties
| Latent Heat of Fusion, J/g | 290 | |
| 320 |
| Maximum Temperature: Mechanical, °C | 940 | |
| 980 |
| Melting Completion (Liquidus), °C | 1430 | |
| 1340 |
| Melting Onset (Solidus), °C | 1380 | |
| 1270 |
| Specific Heat Capacity, J/kg-K | 480 | |
| 440 |
| Thermal Expansion, µm/m-K | 17 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 2.4 | |
| 1.5 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 2.8 | |
| 1.6 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 17 | |
| 75 |
| Density, g/cm3 | 7.7 | |
| 8.5 |
| Embodied Carbon, kg CO2/kg material | 3.6 | |
| 13 |
| Embodied Energy, MJ/kg | 51 | |
| 190 |
| Embodied Water, L/kg | 150 | |
| 270 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 280 | |
| 240 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 300 | |
| 300 |
| Stiffness to Weight: Axial, points | 14 | |
| 13 |
| Stiffness to Weight: Bending, points | 25 | |
| 23 |
| Strength to Weight: Axial, points | 27 | |
| 28 |
| Strength to Weight: Bending, points | 23 | |
| 24 |
| Thermal Shock Resistance, points | 16 | |
| 23 |
Alloy Composition
| Aluminum (Al), % | 0 | |
| 0 to 0.35 |
| Carbon (C), % | 0 to 0.080 | |
| 0 to 0.030 |
| Chromium (Cr), % | 17.5 to 19.5 | |
| 19 to 22.5 |
| Iron (Fe), % | 63 to 74.3 | |
| 2.3 to 15.3 |
| Manganese (Mn), % | 3.5 to 6.5 | |
| 0 to 0.35 |
| Molybdenum (Mo), % | 0.5 to 2.0 | |
| 7.0 to 9.5 |
| Nickel (Ni), % | 4.0 to 6.5 | |
| 55 to 59 |
| Niobium (Nb), % | 0.1 to 1.0 | |
| 2.8 to 4.0 |
| Nitrogen (N), % | 0.080 to 0.3 | |
| 0 |
| Phosphorus (P), % | 0 to 0.060 | |
| 0 to 0.015 |
| Silicon (Si), % | 0 to 1.0 | |
| 0 to 0.2 |
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.010 |
| Titanium (Ti), % | 0 | |
| 1.0 to 1.7 |