Grade 21 Titanium vs. Grade 7 Titanium
Both grade 21 titanium and grade 7 titanium are titanium alloys. They have 79% of their average alloy composition in common. There are 28 material properties with values for both materials. Properties with values for just one material (4, in this case) are not shown.
For each property being compared, the top bar is grade 21 titanium and the bottom bar is grade 7 titanium.
Metric UnitsUS Customary Units
Mechanical Properties
| Elastic (Young's, Tensile) Modulus, GPa | 140 | |
| 110 |
| Elongation at Break, % | 9.0 to 17 | |
| 24 |
| Fatigue Strength, MPa | 550 to 660 | |
| 250 |
| Poisson's Ratio | 0.32 | |
| 0.32 |
| Reduction in Area, % | 22 | |
| 34 |
| Shear Modulus, GPa | 51 | |
| 38 |
| Shear Strength, MPa | 550 to 790 | |
| 270 |
| Tensile Strength: Ultimate (UTS), MPa | 890 to 1340 | |
| 420 |
| Tensile Strength: Yield (Proof), MPa | 870 to 1170 | |
| 340 |
Thermal Properties
| Latent Heat of Fusion, J/g | 410 | |
| 420 |
| Maximum Temperature: Mechanical, °C | 310 | |
| 320 |
| Melting Completion (Liquidus), °C | 1740 | |
| 1660 |
| Melting Onset (Solidus), °C | 1690 | |
| 1610 |
| Specific Heat Capacity, J/kg-K | 500 | |
| 540 |
| Thermal Conductivity, W/m-K | 7.5 | |
| 22 |
| Thermal Expansion, µm/m-K | 7.1 | |
| 9.2 |
Otherwise Unclassified Properties
| Density, g/cm3 | 5.4 | |
| 4.5 |
| Embodied Carbon, kg CO2/kg material | 32 | |
| 47 |
| Embodied Energy, MJ/kg | 490 | |
| 800 |
| Embodied Water, L/kg | 180 | |
| 470 |
Common Calculations
| Resilience: Ultimate (Unit Rupture Work), MJ/m3 | 110 to 180 | |
| 95 |
| Resilience: Unit (Modulus of Resilience), kJ/m3 | 2760 to 5010 | |
| 560 |
| Stiffness to Weight: Axial, points | 14 | |
| 13 |
| Stiffness to Weight: Bending, points | 32 | |
| 35 |
| Strength to Weight: Axial, points | 46 to 69 | |
| 26 |
| Strength to Weight: Bending, points | 38 to 50 | |
| 28 |
| Thermal Diffusivity, mm2/s | 2.8 | |
| 8.9 |
| Thermal Shock Resistance, points | 66 to 100 | |
| 31 |
Alloy Composition
| Aluminum (Al), % | 2.5 to 3.5 | |
| 0 |
| Carbon (C), % | 0 to 0.050 | |
| 0 to 0.080 |
| Hydrogen (H), % | 0 to 0.015 | |
| 0 to 0.015 |
| Iron (Fe), % | 0 to 0.4 | |
| 0 to 0.3 |
| Molybdenum (Mo), % | 14 to 16 | |
| 0 |
| Niobium (Nb), % | 2.2 to 3.2 | |
| 0 |
| Nitrogen (N), % | 0 to 0.030 | |
| 0 to 0.030 |
| Oxygen (O), % | 0 to 0.17 | |
| 0 to 0.25 |
| Palladium (Pd), % | 0 | |
| 0.12 to 0.25 |
| Silicon (Si), % | 0.15 to 0.25 | |
| 0 |
| Titanium (Ti), % | 76 to 81.2 | |
| 98.7 to 99.88 |
| Residuals, % | 0 | |
| 0 to 0.4 |