Hardened SAE-AISI L2 vs. Hardened SAE-AISI S4
Both hardened SAE-AISI L2 and hardened SAE-AISI S4 are iron alloys. Both are furnished in the hardened (H) condition. They have a very high 98% of their average alloy composition in common.
For each property being compared, the top bar is hardened SAE-AISI L2 and the bottom bar is hardened SAE-AISI S4.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 | 
| Poisson's Ratio | 0.29 | |
| 0.29 | 
| Rockwell C Hardness | 60 | |
| 66 | 
| Shear Modulus, GPa | 72 | |
| 72 | 
| Tensile Strength: Ultimate (UTS), MPa | 1960 | |
| 2140 | 
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 280 | 
| Melting Completion (Liquidus), °C | 1450 | |
| 1430 | 
| Melting Onset (Solidus), °C | 1410 | |
| 1390 | 
| Specific Heat Capacity, J/kg-K | 470 | |
| 480 | 
| Thermal Conductivity, W/m-K | 44 | |
| 44 | 
| Thermal Expansion, µm/m-K | 12 | |
| 13 | 
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.3 | |
| 7.4 | 
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.4 | |
| 8.7 | 
Otherwise Unclassified Properties
| Base Metal Price, % relative | 2.4 | |
| 2.2 | 
| Density, g/cm3 | 7.8 | |
| 7.7 | 
| Embodied Carbon, kg CO2/kg material | 1.9 | |
| 2.0 | 
| Embodied Energy, MJ/kg | 27 | |
| 29 | 
| Embodied Water, L/kg | 51 | |
| 48 | 
Common Calculations
| Stiffness to Weight: Axial, points | 13 | |
| 13 | 
| Stiffness to Weight: Bending, points | 24 | |
| 25 | 
| Strength to Weight: Axial, points | 70 | |
| 77 | 
| Strength to Weight: Bending, points | 45 | |
| 48 | 
| Thermal Diffusivity, mm2/s | 12 | |
| 12 | 
| Thermal Shock Resistance, points | 65 | |
| 65 | 
Alloy Composition
| Carbon (C), % | 0.45 to 1.0 | |
| 0.5 to 0.65 | 
| Chromium (Cr), % | 0.7 to 1.2 | |
| 0.1 to 0.5 | 
| Copper (Cu), % | 0 to 0.25 | |
| 0 | 
| Iron (Fe), % | 95.5 to 98.7 | |
| 95.2 to 96.9 | 
| Manganese (Mn), % | 0.1 to 0.9 | |
| 0.6 to 1.0 | 
| Molybdenum (Mo), % | 0 to 0.25 | |
| 0 | 
| Phosphorus (P), % | 0 to 0.030 | |
| 0 to 0.030 | 
| Silicon (Si), % | 0 to 0.5 | |
| 1.8 to 2.3 | 
| Sulfur (S), % | 0 to 0.030 | |
| 0 to 0.030 | 
| Vanadium (V), % | 0.1 to 0.3 | |
| 0.15 to 0.35 |