Grade 3 (3.7055, R50550) Titanium
Grade 3 titanium is a titanium alloy formulated for primary forming into wrought products. Cited properties are appropriate for the annealed condition. 3.7055 is the EN numeric designation for this material. R50550 is the UNS number. Additionally, the ASTM designation is Titanium Grade 3.
This material is well established: the Further Reading section below cites a number of published standards, and that list is not necessarily exhaustive.
It has a moderately low embodied energy among the wrought titaniums in the database.
The graph bars on the material properties cards below compare grade 3 titanium 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
Brinell Hardness
170
Elastic (Young's, Tensile) Modulus
110 GPa 15 x 106 psi
Elongation at Break
21 %
Fatigue Strength
300 MPa 44 x 103 psi
Impact Strength: V-Notched Charpy
62 J 46 ft-lb
Poisson's Ratio
0.32
Reduction in Area
34 %
Shear Modulus
39 GPa 5.7 x 106 psi
Shear Strength
320 MPa 47 x 103 psi
Tensile Strength: Ultimate (UTS)
510 MPa 74 x 103 psi
Tensile Strength: Yield (Proof)
440 MPa 64 x 103 psi
Thermal Properties
Latent Heat of Fusion
420 J/g
Maximum Temperature: Mechanical
320 °C 600 °F
Melting Completion (Liquidus)
1660 °C 3020 °F
Melting Onset (Solidus)
1610 °C 2930 °F
Specific Heat Capacity
540 J/kg-K 0.13 BTU/lb-°F
Thermal Conductivity
21 W/m-K 12 BTU/h-ft-°F
Thermal Expansion
9.2 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
3.3 % IACS
Electrical Conductivity: Equal Weight (Specific)
6.6 % IACS
Otherwise Unclassified Properties
Base Metal Price
37 % relative
Density
4.5 g/cm3 280 lb/ft3
Embodied Carbon
31 kg CO2/kg material
Embodied Energy
510 MJ/kg 220 x 103 BTU/lb
Embodied Water
110 L/kg 13 gal/lb
Common Calculations
Resilience: Ultimate (Unit Rupture Work)
100 MJ/m3
Resilience: Unit (Modulus of Resilience)
910 kJ/m3
Stiffness to Weight: Axial
13 points
Stiffness to Weight: Bending
35 points
Strength to Weight: Axial
32 points
Strength to Weight: Bending
32 points
Thermal Diffusivity
8.6 mm2/s
Thermal Shock Resistance
37 points
Alloy Composition
| Ti | 98.8 to 100 | |
| O | 0 to 0.35 | |
| Fe | 0 to 0.3 | |
| C | 0 to 0.080 | |
| N | 0 to 0.050 | |
| H | 0 to 0.015 | |
| res. | 0 to 0.4 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM F67: Standard Specification for Unalloyed Titanium, for Surgical Implant Applications (UNS R50250, UNS R50400, UNS R50550, UNS R50700)
ISO 5832-2: Implants for surgery - Metallic materials - Part 2: Unalloyed titanium
ASTM B861: Standard Specification for Titanium and Titanium Alloy Seamless Pipe
ASTM B381: Standard Specification for Titanium and Titanium Alloy Forgings
ASTM B265: Standard Specification for Titanium and Titanium Alloy Strip, Sheet, and Plate
ASTM B348: Standard Specification for Titanium and Titanium Alloy Bars and Billets
Titanium and Titanium Alloys: Fundamentals and Applications, Christoph Leyens and Manfred Peters (editors), 2003
Titanium, 2nd ed., G. Lutjering and J. C. Williams, 2007
Sintering of Advanced Materials: Fundamentals and Processes, Zhigang Zak Fang (editor), 2010
Environmental Degradation of Advanced and Traditional Engineering Materials, Lloyd H. Hihara et al., 2014.