Grade 21 Titanium vs. 771.0 Aluminum
Grade 21 titanium belongs to the titanium alloys classification, while 771.0 aluminum belongs to the aluminum alloys. There are 27 material properties with values for both materials. Properties with values for just one material (6, in this case) are not shown.
For each property being compared, the top bar is grade 21 titanium and the bottom bar is 771.0 aluminum.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 140 | |
| 70 |
| Elongation at Break, % | 9.0 to 17 | |
| 1.7 to 6.5 |
| Fatigue Strength, MPa | 550 to 660 | |
| 92 to 180 |
| Poisson's Ratio | 0.32 | |
| 0.32 |
| Shear Modulus, GPa | 51 | |
| 26 |
| Tensile Strength: Ultimate (UTS), MPa | 890 to 1340 | |
| 250 to 370 |
| Tensile Strength: Yield (Proof), MPa | 870 to 1170 | |
| 210 to 350 |
Thermal Properties
| Latent Heat of Fusion, J/g | 410 | |
| 380 |
| Maximum Temperature: Mechanical, °C | 310 | |
| 180 |
| Melting Completion (Liquidus), °C | 1740 | |
| 630 |
| Melting Onset (Solidus), °C | 1690 | |
| 620 |
| Specific Heat Capacity, J/kg-K | 500 | |
| 870 |
| Thermal Conductivity, W/m-K | 7.5 | |
| 140 to 150 |
| Thermal Expansion, µm/m-K | 7.1 | |
| 24 |
Otherwise Unclassified Properties
| Base Metal Price, % relative | 60 | |
| 9.5 |
| Density, g/cm3 | 5.4 | |
| 3.0 |
| Embodied Carbon, kg CO2/kg material | 32 | |
| 8.0 |
| Embodied Energy, MJ/kg | 490 | |
| 150 |
| Embodied Water, L/kg | 180 | |
| 1130 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 110 to 180 | |
| 4.4 to 20 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 2760 to 5010 | |
| 310 to 900 |
| Stiffness to Weight: Axial, points | 14 | |
| 13 |
| Stiffness to Weight: Bending, points | 32 | |
| 46 |
| Strength to Weight: Axial, points | 46 to 69 | |
| 23 to 35 |
| Strength to Weight: Bending, points | 38 to 50 | |
| 29 to 39 |
| Thermal Diffusivity, mm2/s | 2.8 | |
| 54 to 58 |
| Thermal Shock Resistance, points | 66 to 100 | |
| 11 to 16 |
Alloy Composition
| Aluminum (Al), % | 2.5 to 3.5 | |
| 90.5 to 92.5 |
| Carbon (C), % | 0 to 0.050 | |
| 0 |
| Chromium (Cr), % | 0 | |
| 0.060 to 0.2 |
| Copper (Cu), % | 0 | |
| 0 to 0.1 |
| Hydrogen (H), % | 0 to 0.015 | |
| 0 |
| Iron (Fe), % | 0 to 0.4 | |
| 0 to 0.15 |
| Magnesium (Mg), % | 0 | |
| 0.8 to 1.0 |
| Manganese (Mn), % | 0 | |
| 0 to 0.1 |
| Molybdenum (Mo), % | 14 to 16 | |
| 0 |
| Niobium (Nb), % | 2.2 to 3.2 | |
| 0 |
| Nitrogen (N), % | 0 to 0.030 | |
| 0 |
| Oxygen (O), % | 0 to 0.17 | |
| 0 |
| Silicon (Si), % | 0.15 to 0.25 | |
| 0 to 0.15 |
| Titanium (Ti), % | 76 to 81.2 | |
| 0.1 to 0.2 |
| Zinc (Zn), % | 0 | |
| 6.5 to 7.5 |
| Residuals, % | 0 | |
| 0 to 0.15 |