SAE-AISI 4340 Steel vs. EN 1.4421 Stainless Steel
Both SAE-AISI 4340 steel and EN 1.4421 stainless steel are iron alloys. They have 81% of their average alloy composition in common. 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 4340 steel and the bottom bar is EN 1.4421 stainless steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 200 |
| Elongation at Break, % | 12 to 22 | |
| 11 to 17 |
| Fatigue Strength, MPa | 330 to 740 | |
| 380 to 520 |
| Poisson's Ratio | 0.29 | |
| 0.28 |
| Shear Modulus, GPa | 73 | |
| 77 |
| Tensile Strength: Ultimate (UTS), MPa | 690 to 1280 | |
| 880 to 1100 |
| Tensile Strength: Yield (Proof), MPa | 470 to 1150 | |
| 620 to 950 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 280 |
| Maximum Temperature: Mechanical, °C | 430 | |
| 870 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1440 |
| Melting Onset (Solidus), °C | 1420 | |
| 1400 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 480 |
| Thermal Conductivity, W/m-K | 44 | |
| 16 |
| Thermal Expansion, µm/m-K | 13 | |
| 10 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.5 | |
| 2.2 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.6 | |
| 2.5 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 3.5 | |
| 12 |
| Density, g/cm3 | 7.8 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 1.7 | |
| 2.6 |
| Embodied Energy, MJ/kg | 22 | |
| 36 |
| Embodied Water, L/kg | 53 | |
| 130 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 79 to 170 | |
| 120 to 140 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 590 to 3490 | |
| 960 to 2270 |
| Stiffness to Weight: Axial, points | 13 | |
| 14 |
| Stiffness to Weight: Bending, points | 24 | |
| 25 |
| Strength to Weight: Axial, points | 24 to 45 | |
| 31 to 39 |
| Strength to Weight: Bending, points | 22 to 33 | |
| 26 to 30 |
| Thermal Diffusivity, mm2/s | 12 | |
| 4.4 |
| Thermal Shock Resistance, points | 20 to 38 | |
| 31 to 39 |
Alloy Composition
| Carbon (C), % | 0.38 to 0.43 | |
| 0 to 0.060 |
| Chromium (Cr), % | 0.7 to 0.9 | |
| 15.5 to 17.5 |
| Iron (Fe), % | 95.1 to 96.3 | |
| 74.4 to 80.5 |
| Manganese (Mn), % | 0.6 to 0.8 | |
| 0 to 1.0 |
| Molybdenum (Mo), % | 0.2 to 0.3 | |
| 0 to 0.7 |
| Nickel (Ni), % | 1.7 to 2.0 | |
| 4.0 to 5.5 |
| Phosphorus (P), % | 0 to 0.035 | |
| 0 to 0.035 |
| Silicon (Si), % | 0.15 to 0.35 | |
| 0 to 0.8 |
| Sulfur (S), % | 0 to 0.040 | |
| 0 to 0.020 |