Titanium 6-7 (R56700)
Titanium 6-7 is a titanium alloy formulated for primary forming into wrought products. Cited properties are appropriate for the annealed condition. R56700 is the UNS number for this material. Titanium 6-7 is the common industry name.
It has the highest base cost among wrought titaniums. In addition, it has a fairly high density and a fairly high melting temperature.
The graph bars on the material properties cards below compare titanium 6-7 to: wrought titaniums (top), all titanium alloys (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Elastic (Young's, Tensile) Modulus
120 GPa 17 x 106 psi
Elongation at Break
11 %
Fatigue Strength
530 MPa 77 x 103 psi
Poisson's Ratio
0.33
Reduction in Area
29 %
Shear Modulus
45 GPa 6.5 x 106 psi
Shear Strength
610 MPa 88 x 103 psi
Tensile Strength: Ultimate (UTS)
1020 MPa 150 x 103 psi
Tensile Strength: Yield (Proof)
900 MPa 130 x 103 psi
Thermal Properties
Latent Heat of Fusion
410 J/g
Maximum Temperature: Mechanical
300 °C 580 °F
Melting Completion (Liquidus)
1700 °C 3100 °F
Melting Onset (Solidus)
1650 °C 3000 °F
Specific Heat Capacity
520 J/kg-K 0.13 BTU/lb-°F
Thermal Expansion
9.3 µm/m-K
Otherwise Unclassified Properties
Base Metal Price
75 % relative
Density
5.1 g/cm3 320 lb/ft3
Embodied Carbon
34 kg CO2/kg material
Embodied Energy
540 MJ/kg 230 x 103 BTU/lb
Embodied Water
190 L/kg 23 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
110 MJ/m3
Resilience: Unit (Modulus of Resilience)
3460 kJ/m3
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
32 points
Strength to Weight: Axial
56 points
Strength to Weight: Bending
44 points
Thermal Shock Resistance
66 points
Alloy Composition
| Ti | 84.9 to 88 | |
| Mo | 6.5 to 7.5 | |
| Nb | 6.5 to 7.5 | |
| Al | 5.5 to 6.5 | |
| Ta | 0 to 0.5 | |
| Fe | 0 to 0.25 | |
| O | 0 to 0.2 | |
| C | 0 to 0.080 | |
| N | 0 to 0.050 | |
| H | 0 to 0.0090 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM F1295: Standard Specification for Wrought Titanium-6 Aluminum-7 Niobium Alloy for Surgical Implant Applications (UNS R56700)
Titanium and Titanium Alloys: Fundamentals and Applications, Christoph Leyens and Manfred Peters (editors), 2003
Titanium, 2nd ed., G. Lutjering and J. C. Williams, 2007
CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015