SAE-AISI 1045 Steel vs. SAE-AISI 4340M Steel
Both SAE-AISI 1045 steel and SAE-AISI 4340M steel are iron alloys. They have a very high 95% of their average alloy composition in common. There are 31 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 1045 steel and the bottom bar is SAE-AISI 4340M steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 180 to 190 | |
| 710 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 13 to 18 | |
| 6.0 |
| Fatigue Strength, MPa | 220 to 370 | |
| 690 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Shear Modulus, GPa | 72 | |
| 72 |
| Shear Strength, MPa | 380 to 410 | |
| 1360 |
| Tensile Strength: Ultimate (UTS), MPa | 620 to 680 | |
| 2340 |
| Tensile Strength: Yield (Proof), MPa | 330 to 580 | |
| 1240 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 280 |
| Maximum Temperature: Mechanical, °C | 400 | |
| 430 |
| 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 | 51 | |
| 38 |
| Thermal Expansion, µm/m-K | 12 | |
| 13 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.0 | |
| 7.8 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.1 | |
| 9.1 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 1.8 | |
| 3.9 |
| Density, g/cm3 | 7.8 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 1.4 | |
| 1.9 |
| Embodied Energy, MJ/kg | 18 | |
| 26 |
| Embodied Water, L/kg | 46 | |
| 55 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 84 to 93 | |
| 120 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 300 to 900 | |
| 4120 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 25 |
| Strength to Weight: Axial, points | 22 to 24 | |
| 84 |
| Strength to Weight: Bending, points | 21 to 22 | |
| 51 |
| Thermal Diffusivity, mm2/s | 14 | |
| 10 |
| Thermal Shock Resistance, points | 20 to 22 | |
| 70 |
Alloy Composition
| Carbon (C), % | 0.43 to 0.5 | |
| 0.38 to 0.43 |
| Chromium (Cr), % | 0 | |
| 0.7 to 1.0 |
| Iron (Fe), % | 98.5 to 99 | |
| 93.3 to 94.8 |
| Manganese (Mn), % | 0.6 to 0.9 | |
| 0.65 to 0.9 |
| Molybdenum (Mo), % | 0 | |
| 0.35 to 0.45 |
| Nickel (Ni), % | 0 | |
| 1.7 to 2.0 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.012 |
| Silicon (Si), % | 0 | |
| 1.5 to 1.8 |
| Sulfur (S), % | 0 to 0.050 | |
| 0 to 0.012 |
| Vanadium (V), % | 0 | |
| 0.050 to 0.1 |