ASTM A321 Carbon Steel vs. SAE-AISI 1055 Steel
Both ASTM A321 carbon steel and SAE-AISI 1055 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 1055 steel.
Metric UnitsUS Customary Units
Mechanical Properties
| Brinell Hardness | 190 | |
| 220 |
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 190 |
| Elongation at Break, % | 21 | |
| 11 to 14 |
| Fatigue Strength, MPa | 270 | |
| 260 to 390 |
| Poisson's Ratio | 0.29 | |
| 0.29 |
| Reduction in Area, % | 39 | |
| 34 to 45 |
| Shear Modulus, GPa | 73 | |
| 72 |
| Shear Strength, MPa | 420 | |
| 440 to 450 |
| Tensile Strength: Ultimate (UTS), MPa | 670 | |
| 730 to 750 |
| Tensile Strength: Yield (Proof), MPa | 390 | |
| 400 to 630 |
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 | |
| 11 |
| Electrical Conductivity: Equal Weight (Specific), % IACS | 8.1 | |
| 12 |
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 | |
| 80 to 85 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 400 | |
| 440 to 1070 |
| Stiffness to Weight: Axial, points | 13 | |
| 13 |
| Stiffness to Weight: Bending, points | 24 | |
| 24 |
| Strength to Weight: Axial, points | 24 | |
| 26 |
| Strength to Weight: Bending, points | 22 | |
| 23 |
| Thermal Diffusivity, mm2/s | 14 | |
| 14 |
| Thermal Shock Resistance, points | 21 | |
| 23 to 24 |
Alloy Composition
| Carbon (C), % | 0 to 0.55 | |
| 0.5 to 0.6 |
| Iron (Fe), % | 98.1 to 99.25 | |
| 98.4 to 98.9 |
| 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 |