SAE-AISI 4340 Steel vs. ASTM A266 Carbon Steel
Both SAE-AISI 4340 steel and ASTM A266 carbon steel are iron alloys. There are 31 material properties with values for both materials. Properties with values for just one material (1, in this case) are not shown.
For each property being compared, the top bar is SAE-AISI 4340 steel and the bottom bar is ASTM A266 carbon steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 210 to 360 | |
| 150 to 180 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 12 to 22 | |
| 21 to 26 |
| Fatigue Strength, MPa | 330 to 740 | |
| 170 to 200 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 73 | |
| 73 |
| Shear Strength, MPa | 430 to 770 | |
| 320 to 380 |
| Tensile Strength: Ultimate (UTS), MPa | 690 to 1280 | |
| 500 to 600 |
| Tensile Strength: Yield (Proof), MPa | 470 to 1150 | |
| 230 to 290 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 250 |
| Maximum Temperature: Mechanical, °C | 430 | |
| 400 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1460 |
| Melting Onset (Solidus), °C | 1420 | |
| 1420 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 470 |
| Thermal Conductivity, W/m-K | 44 | |
| 51 to 52 |
| Thermal Expansion, µm/m-K | 13 | |
| 12 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.5 | |
| 7.1 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.6 | |
| 8.1 to 8.2 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 3.5 | |
| 1.8 |
| Density, g/cm3 | 7.8 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 1.7 | |
| 1.4 |
| Embodied Energy, MJ/kg | 22 | |
| 18 to 19 |
| Embodied Water, L/kg | 53 | |
| 46 to 47 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 79 to 170 | |
| 110 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 590 to 3490 | |
| 140 to 230 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 24 to 45 | |
| 18 to 21 |
| Strength to Weight: Bending, points | 22 to 33 | |
| 18 to 20 |
| Thermal Diffusivity, mm2/s | 12 | |
| 14 |
| Thermal Shock Resistance, points | 20 to 38 | |
| 16 to 19 |