Titanium 6Al-6V-2Sn (Ti-6-6-2) is a high-strength, heat-treatable alpha-beta titanium alloy derived from Ti-6Al-4V. By increasing vanadium and adding tin, this alloy achieves superior hardenability, elevated-temperature strength, and fatigue resistance.
Typical Chemical Composition
| Element | Typical % |
|---|---|
| Titanium (Ti) | Balance |
| Aluminum (Al) | 5.0 – 6.0 |
| Vanadium (V) | 5.0 – 6.0 |
| Tin (Sn) | 1.5 – 2.5 |
| Iron (Fe) | 0.35 – 1.0 |
| Copper (Cu) | ≤ 1.0 |
| O, N, H | Controlled trace levels |
Metallurgy & Microstructure
Ti-6-6-2 is an α + β titanium alloy featuring fine alpha particles uniformly distributed within a beta matrix. This microstructure provides an excellent balance of strength, temperature stability, and fatigue performance.
Mechanical & Physical Properties
| Property | Typical Value |
|---|---|
| Tensile Strength | 1000 – 1100 MPa |
| Yield Strength | 950 – 1035 MPa |
| Elongation | 10 – 15% |
| Density | ~4.54 g/cm³ |
| Service Temperature | Up to ~500 °C |
Key Advantages
✔ Very high strength-to-weight ratio
✔ Heat treatable (solution treated & aged)
✔ Excellent fatigue resistance
✔ Strong corrosion & oxidation resistance
✔ Retains strength at elevated temperatures
Limitations
⚠ Lower toughness than Ti-6Al-4V
⚠ Limited weldability (forging & machining preferred)
⚠ Higher material and processing cost
Typical Applications
Aerospace & Defense
Airframes, jet engine components, rocket casings, critical fasteners
Space & Launch Vehicles
High-strength, lightweight structural components
Energy & Industrial
High-stress shafts, pressure vessels, nuclear and turbine components
Why Choose Ti-6Al-6V-2Sn?
Ti-6-6-2 is selected when extreme strength, fatigue resistance, and elevated-temperature performance are required at minimal weight. It is engineered for high-value, safety-critical applications where performance outweighs cost.
In simple words:
If Ti-6Al-4V is not strong enough, Ti-6-6-2 is the next step for
aerospace-grade performance.