Titanium Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed
Heat-treated state · default condition
Standard stocked condition for bar, billet, forgings and sheet: balanced strength, ductility and creep life.
Values for the Duplex Annealed condition
Other Ti-6Al-2Sn-4Zr-2Mo-0.1Si tempers and conditions
Ti-6Al-2Sn-4Zr-2Mo-0.1Si is listed in 7 conditions; see the grade overview at Ti-6Al-2Sn-4Zr-2Mo-0.1Si.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
heated above beta transus (~1010–1040 °C), cooled, then stabilised | Transformed (Widmanstätten/basketweave) structure for maximum fracture toughness, creep and crack-growth resistance in discs and casings. | 890 | 970 | 12 | 32 HRC | 0.87 % IACS |
beta solution treated, cooled and overaged/stabilised (~595–650 °C) | Used for creep- and dwell-fatigue-critical engine hardware where dimensional stability after long hot exposure matters. | 900 | 1,000 | 11 | 33 HRC | 0.87 % IACS |
As-welded (GTAW/EBW joint, post-weld stress relief 540–650 °C) | Reference condition for fusion-welded rings and cases; joint strength approaches base metal but ductility drops. | 900 | 980 | 8 | 33 HRC | 0.87 % IACS |
790–815 °C, 1–2 h, air cool | Cheaper as-supplied condition for sheet and plate where full creep optimisation is not required. | 910 | 1,000 | 14 | 31 HRC | 0.87 % IACS |
As-forged + duplex annealed | Typical supply condition for compressor discs, impellers and rings forged below the beta transus. | 925 | 1,000 | 14 | 32 HRC | 0.87 % IACS |
Duplex AnnealedDefaultThis page 900–925 °C air cool + 790 °C/8 h stabilise | Standard stocked condition for bar, billet, forgings and sheet: balanced strength, ductility and creep life. | 930 | 1,010 | 15 | 32 HRC | — |
Solution treated and aged | Choose when peak room- and mid-temperature strength is needed in thinner sections, accepting lower toughness. | 1,000 | 1,100 | 12 | 35 HRC | — |
What is Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed?
Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed is Ti-6Al-2Sn-4Zr-2Mo-0.1Si heat treated to Duplex Annealed — standard stocked condition for bar, billet, forgings and sheet: balanced strength, ductility and creep life. Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed has a yield strength of 930 MPa (135 ksi) and a tensile strength of 1,010 MPa (146 ksi) — stronger than 86% of titanium grades. Elongation at break is 15% and the elastic modulus is 114 GPa (16.5 Msi). Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed has a density of 4.54 g/cm³ (0.164 lb/in³), heavier than 80% of titanium grades. It melts at 1,650°C (3,002 °F).
Advantages
- High service temperature — 510°C (950 °F), better than 96% of titanium grades
- High strength — 930 MPa (135 ksi), better than 86% of titanium grades
Limitations
- Low electrical conductivity — 0.87 % IACS, worse than 100% of titanium grades
- Low fracture toughness — 55 MPa·√m (50.1 ksi·√in), worse than 90% of titanium grades
- Difficult to weld — 65/100, worse than 77% of titanium grades
Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed properties
Typical room-temperature values for Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed; 11 are specific to this condition. Other listed values are Ti-6Al-2Sn-4Zr-2Mo-0.1Si reference data and may not represent this condition. Bars are the position among titanium grades.
Physical3
Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed has a density of 4.54 g/cm³ (0.164 lb/in³), heavier than 80% of titanium grades. It melts at 1,650°C (3,002 °F).
Mechanical16
Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed has a yield strength of 930 MPa (135 ksi) and a tensile strength of 1,010 MPa (146 ksi) — stronger than 86% of titanium grades. Elongation at break is 15% and the elastic modulus is 114 GPa (16.5 Msi).
Thermal6
Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed is rated for continuous service to 510°C (950 °F). It conducts heat at 7 W/m·K (4.04 BTU/hr·ft·°F), worse than 76% of titanium grades. Thermal expansion is 7.7 µm/m·K (4.28 µin/in·°F).
Electrical3
Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed conducts electricity at 0.87 % IACS, worse than 100% of titanium grades.
Chemical & Environmental3
Corrosion resistance is excellent (85/100), worse than 93% of titanium grades.
Sustainability4
Producing a kilogram of Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed takes about 680 MJ of energy and emits 40 kg of CO₂ — more than 51% of titanium grades. Typical recycled content is 25%.
Manufacturability8
Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed's machinability is poor (18/100, worse than 83% of titanium grades); weldability good (65/100); formability poor (25/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed
Is Ti-6Al-2Sn-4Zr-2Mo-0.1Si easy to machine?
Machine like a tough near-alpha Ti: rigid setups, sharp uncoated-carbide or PVD-coated tools, low surface speed (~20–40 m/min), heavy positive feed, flood high-pressure coolant, never dwell — work-hardened smearing and chip fires are the main risks.
Can Ti-6Al-2Sn-4Zr-2Mo-0.1Si be welded?
GTAW, plasma, electron-beam and laser welding are practical with full inert-gas or vacuum shielding and clean surfaces; hydrogen/oxygen pickup must be avoided and a 540–650 °C post-weld stress relief is normal.
Can Ti-6Al-2Sn-4Zr-2Mo-0.1Si be formed, bent or molded?
Cold formability is poor; hot form or hot size at 700–870 °C (forge below the ~995–1010 °C beta transus for alpha/beta structure), then chemically mill or grind off alpha case.
What surface finishes work on Ti-6Al-2Sn-4Zr-2Mo-0.1Si?
Grit-blast/pickle to remove alpha case, then conversion anodise (AMS 2488) or shot-peen for fatigue; thermal-spray, nitride or DLC coatings are used for wear and galling since titanium galls against itself.
Ti-6Al-2Sn-4Zr-2Mo-0.1Si chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Al | 5.5 – 6.5 | 6 |
| Sn | 1.8 – 2.2 | 2 |
| Zr | 3.6 – 4.4 | 4 |
| Mo | 1.8 – 2.2 | 2 |
| Sicreep-strengthening addition that distinguishes the 'S' variant | 0.06 – 0.1 | 0.08 |
| Fe | ≤ 0.25 | — |
| Omax; often 0.10–0.12 for creep grades | ≤ 0.15 | 0.11 |
| C | ≤ 0.05 | — |
| N | ≤ 0.05 | — |
| Hmax (bar/forging) | ≤ 0.01 | — |
| Ymax, aerospace melt cleanliness | ≤ 0.01 | — |
| other, eachresiduals total 0.40 max | ≤ 0.1 | — |
| Ti | balance | — |
Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed — frequently asked
What is Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed used for?
Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed is typically used for turbine engine compressor discs, compressor blades and blisks, engine casings and spacer rings, forged rings and shafts for engines, high-temperature airframe structure and sheet-metal exhaust and nozzle structures. In short: creep resistant to 510 °C; silicon-modified Ti-6242; hot-section engine alloy.
What is the yield strength of Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed?
Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed has a typical yield strength of 930 MPa (135 ksi) and a tensile strength of 1,010 MPa (146 ksi) — stronger than 86% of titanium grades. Strength varies by condition: see the 7 listed tempers.
Is Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed easy to machine?
Not especially — machinability is rated poor (18/100, worse than 83% of titanium grades). Machine like a tough near-alpha Ti: rigid setups, sharp uncoated-carbide or PVD-coated tools, low surface speed (~20–40 m/min), heavy positive feed, flood high-pressure coolant, never dwell — work-hardened smearing and chip fires are the main risks.
Can Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed be welded?
Yes — weldability is rated good (65/100). GTAW, plasma, electron-beam and laser welding are practical with full inert-gas or vacuum shielding and clean surfaces; hydrogen/oxygen pickup must be avoided and a 540–650 °C post-weld stress relief is normal.
What surface finishes work on Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed?
Grit-blast/pickle to remove alpha case, then conversion anodise (AMS 2488) or shot-peen for fatigue; thermal-spray, nitride or DLC coatings are used for wear and galling since titanium galls against itself.
Can Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed be formed, bent or molded?
Cold formability is poor; hot form or hot size at 700–870 °C (forge below the ~995–1010 °C beta transus for alpha/beta structure), then chemically mill or grind off alpha case.
What is the maximum service temperature of Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed?
Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed is rated for continuous use to about 510°C (950 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Ti-6Al-2Sn-4Zr-2Mo-0.1Si Duplex Annealed and Ti-6Al-2Sn-4Zr-2Mo-0.1Si-STA?
Duplex Annealed is the default condition — standard stocked condition for bar, billet, forgings and sheet: balanced strength, ductility and creep life. STA: choose when peak room- and mid-temperature strength is needed in thinner sections, accepting lower toughness. Yield strength is 930 MPa in Duplex Annealed versus 1,000 MPa in STA.
Sources
- AMS 4975 — Ti-6Al-2Sn-4Zr-2Mo bar, forgings and rings — SAE International (2021)
- AMS 4919 — Ti-6Al-2Sn-4Zr-2Mo sheet, strip and plate, duplex annealed — SAE International (2017)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- Materials Properties Handbook: Titanium Alloys — ASM International (1994)
- MMPDS — Metallic Materials Properties Development and Standardization — Battelle/FAA (2019)
- TIMETAL 6-2-4-2 alloy datasheet — TIMET (2020)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.