ASTM A321 Carbon Steel vs. SAE-AISI 1045 Steel
Both ASTM A321 carbon steel and SAE-AISI 1045 steel are iron alloys. Their average alloy composition is basically identical.
For each property being compared, the top bar is ASTM A321 carbon steel and the bottom bar is SAE-AISI 1045 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 190 | |
| 180 to 190 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 21 | |
| 13 to 18 |
| Fatigue Strength, MPa | 270 | |
| 220 to 370 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Reduction in Area, % | 39 | |
| 40 to 51 |
| Shear Modulus, GPa | 73 | |
| 72 |
| Shear Strength, MPa | 420 | |
| 380 to 410 |
| Tensile Strength: Ultimate (UTS), MPa | 670 | |
| 620 to 680 |
| Tensile Strength: Yield (Proof), MPa | 390 | |
| 330 to 580 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 250 |
| Maximum Temperature: Mechanical, °C | 400 | |
| 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 | 51 | |
| 51 |
| Thermal Expansion, µm/m-K | 12 | |
| 12 |
Electrical Properties
| Electrical Conductivity: Equal Volume, % IACS | 7.1 | |
| 7.0 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.1 | |
| 8.1 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 1.8 | |
| 1.8 |
| Density, g/cm3 | 7.8 | |
| 7.8 |
| Embodied Carbon, kg CO2/kg material | 1.4 | |
| 1.4 |
| Embodied Energy, MJ/kg | 18 | |
| 18 |
| Embodied Water, L/kg | 46 | |
| 46 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 120 | |
| 84 to 93 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 400 | |
| 300 to 900 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 24 | |
| 22 to 24 |
| Strength to Weight: Bending, points | 22 | |
| 21 to 22 |
| Thermal Diffusivity, mm2/s | 14 | |
| 14 |
| Thermal Shock Resistance, points | 21 | |
| 20 to 22 |
Alloy Composition
| Carbon (C), % | 0 to 0.55 | |
| 0.43 to 0.5 |
| Iron (Fe), % | 98.1 to 99.25 | |
| 98.5 to 99 |
| Manganese (Mn), % | 0.6 to 0.9 | |
| 0.6 to 0.9 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 to 0.040 |
| Silicon (Si), % | 0.15 to 0.35 | |
| 0 |
| Sulfur (S), % | 0 to 0.050 | |
| 0 to 0.050 |