SAE-AISI 1018 Steel vs. Grade 21 Titanium
SAE-AISI 1018 steel belongs to the iron alloys classification, while grade 21 titanium belongs to the titanium alloys. There are 29 material properties with values for both materials. Properties with values for just one material (3, in this case) are not shown.
For each property being compared, the top bar is SAE-AISI 1018 steel and the bottom bar is grade 21 titanium.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 190 | |
| 140 |
| Elongation at Break, % | 17 to 27 | |
| 9.0 to 17 |
| Fatigue Strength, MPa | 180 to 270 | |
| 550 to 660 |
| Poisson's Ratio | 0.29 | |
| 0.32 |
| Reduction in Area, % | 45 to 57 | |
| 22 |
| Shear Modulus, GPa | 73 | |
| 51 |
| Shear Strength, MPa | 280 to 300 | |
| 550 to 790 |
| Tensile Strength: Ultimate (UTS), MPa | 430 to 480 | |
| 890 to 1340 |
| Tensile Strength: Yield (Proof), MPa | 240 to 400 | |
| 870 to 1170 |
Thermal Properties
| Latent Heat of Fusion, J/g | 250 | |
| 410 |
| Maximum Temperature: Mechanical, °C | 400 | |
| 310 |
| Melting Completion (Liquidus), °C | 1460 | |
| 1740 |
| Melting Onset (Solidus), °C | 1420 | |
| 1690 |
| Specific Heat Capacity, J/kg-K | 470 | |
| 500 |
| Thermal Conductivity, W/m-K | 52 | |
| 7.5 |
| Thermal Expansion, µm/m-K | 12 | |
| 7.1 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 1.8 | |
| 60 |
| Density, g/cm3 | 7.9 | |
| 5.4 |
| Embodied Carbon, kg CO2/kg material | 1.4 | |
| 32 |
| Embodied Energy, MJ/kg | 18 | |
| 490 |
| Embodied Water, L/kg | 46 | |
| 180 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 75 to 100 | |
| 110 to 180 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 150 to 430 | |
| 2760 to 5010 |
| Stiffness to Weight: Axial, points | 13 | |
| 14 |
| Stiffness to Weight: Bending, points | 24 | |
| 32 |
| Strength to Weight: Axial, points | 15 to 17 | |
| 46 to 69 |
| Strength to Weight: Bending, points | 16 to 17 | |
| 38 to 50 |
| Thermal Diffusivity, mm2/s | 14 | |
| 2.8 |
| Thermal Shock Resistance, points | 14 to 15 | |
| 66 to 100 |
Alloy Composition
| Aluminum (Al), % | 0 | |
| 2.5 to 3.5 |
| Carbon (C), % | 0.15 to 0.2 | |
| 0 to 0.050 |
| Hydrogen (H), % | 0 | |
| 0 to 0.015 |
| Iron (Fe), % | 98.8 to 99.25 | |
| 0 to 0.4 |
| Manganese (Mn), % | 0.6 to 0.9 | |
| 0 |
| Molybdenum (Mo), % | 0 | |
| 14 to 16 |
| Niobium (Nb), % | 0 | |
| 2.2 to 3.2 |
| Nitrogen (N), % | 0 | |
| 0 to 0.030 |
| Oxygen (O), % | 0 | |
| 0 to 0.17 |
| Phosphorus (P), % | 0 to 0.040 | |
| 0 |
| Silicon (Si), % | 0 | |
| 0.15 to 0.25 |
| Sulfur (S), % | 0 to 0.050 | |
| 0 |
| Titanium (Ti), % | 0 | |
| 76 to 81.2 |
| Residuals, % | 0 | |
| 0 to 0.4 |