Titanium Ti Grade 35-STA (Solution treated and aged)
Heat-treated state
UNS R56340 · ASTM Grade 35 · also TIMETAL 62S
Choose for maximum strength in fasteners, springs and thin high-load sections; ductility and toughness drop.
Values for the STA condition
Other Ti Grade 35 tempers and conditions
Ti Grade 35 is listed in 5 conditions; see the grade overview at Ti Grade 35.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Softest, most ductile condition — used as the pre-form state for deep drawing and cold heading before ageing. | 830 | 900 | 20 | 30 HRC | 1 % IACS |
SPF/Annealed | Condition of parts after low-temperature (≈750–800 °C) superplastic forming/diffusion bonding — the alloy's signature application. | 890 | 960 | 15 | 32 HRC | 1 % IACS |
AnnealedDefault mill annealed (typ. 700–780 °C, air cool) | Standard stocked condition for sheet, plate and bar; best balance of strength, ductility and toughness. | 920 | 990 | 16 | 33 HRC | — |
Cold worked | As-cold-rolled strip or drawn wire; higher strength with reduced ductility, normally stress-relieved or annealed before use. | 1,050 | 1,120 | 8 | 36 HRC | 1 % IACS |
STAThis page Solution treated and aged | Choose for maximum strength in fasteners, springs and thin high-load sections; ductility and toughness drop. | 1,200 | 1,290 | 9 | 40 HRC | — |
What is Ti Grade 35-STA?
Ti Grade 35-STA is Ti Grade 35 heat treated to STA — choose for maximum strength in fasteners, springs and thin high-load sections; ductility and toughness drop. Ti Grade 35-STA has a yield strength of 1,200 MPa (174 ksi) and a tensile strength of 1,290 MPa (187 ksi) — stronger than 100% of titanium grades. Elongation at break is 9% and the elastic modulus is 114 GPa (16.5 Msi). Ti Grade 35-STA has a density of 4.54 g/cm³ (0.164 lb/in³), heavier than 80% of titanium grades. It melts at 1,590°C (2,894 °F). Annealed is the default condition FabDigit quotes; STA is available on request or by drawing note.
Advantages
- High strength — 1,200 MPa (174 ksi), better than 100% of titanium grades
Limitations
- Difficult to machine — 14/100, worse than 100% of titanium grades
- Limited ductility — 9%, worse than 97% of titanium grades
- Low fracture toughness — 50 MPa·√m (45.5 ksi·√in), worse than 96% of titanium grades
- Low electrical conductivity — 1 % IACS, worse than 89% of titanium grades
- Difficult to weld — 55/100, worse than 87% of titanium grades
Ti Grade 35-STA properties
Typical room-temperature values for Ti Grade 35-STA; 15 are specific to this condition. Other listed values are Ti Grade 35 reference data and may not represent this condition. Bars are the position among titanium grades.
Physical3
Ti Grade 35-STA has a density of 4.54 g/cm³ (0.164 lb/in³), heavier than 80% of titanium grades. It melts at 1,590°C (2,894 °F).
Mechanical16
Ti Grade 35-STA has a yield strength of 1,200 MPa (174 ksi) and a tensile strength of 1,290 MPa (187 ksi) — stronger than 100% of titanium grades. Elongation at break is 9% and the elastic modulus is 114 GPa (16.5 Msi).
Thermal6
Ti Grade 35-STA is rated for continuous service to 315°C (599 °F). It conducts heat at 7 W/m·K (4.04 BTU/hr·ft·°F), worse than 76% of titanium grades. Thermal expansion is 9.4 µm/m·K (5.22 µin/in·°F).
Electrical3
Ti Grade 35-STA conducts electricity at 1 % IACS, worse than 89% of titanium grades.
Chemical & Environmental3
Corrosion resistance is excellent (85/100), worse than 93% of titanium grades.
Sustainability4
Producing a kilogram of Ti Grade 35-STA takes about 680 MJ of energy and emits 44 kg of CO₂ — more than 51% of titanium grades. Typical recycled content is 25%.
Manufacturability8
Ti Grade 35-STA's machinability is not recommended (14/100, worse than 100% of titanium grades); weldability good (55/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Ti Grade 35-STA
Is Ti Grade 35 easy to machine?
Machine like Ti-6Al-4V but ~10–20 % slower: rigid setups, sharp uncoated-carbide or AlTiN tools, 20–40 m/min in the annealed state, heavy flood coolant, never dwell in the cut.
Can Ti Grade 35 be welded?
GTAW, plasma, laser or EB welding in high-purity argon or vacuum with full back-shielding; weld metal is stronger but less ductile than base metal, so post-weld anneal or full STA is recommended.
Can Ti Grade 35 be formed, bent or molded?
Its main selling point — good room-temperature bendability in the ST/annealed condition and superplastic forming at only ~750–800 °C (lower than Ti-6Al-4V), enabling SPF/diffusion-bonded structures with reduced tooling wear.
What surface finishes work on Ti Grade 35?
Descale by grit blast + HNO3/HF pickle after hot work; accepts Type II colour anodising, oxide/anodic conversion coatings for galling resistance, and polishes well due to its fine grain size.
Ti Grade 35 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 | 4 – 5 | 4.5 |
| V | 2.5 – 3.5 | 3 |
| Mo | 1.8 – 2.2 | 2 |
| Febeta stabiliser; responsible for grain refinement and low-temperature SPF | 1.7 – 2.3 | 2 |
| O | ≤ 0.15 | 0.1 |
| C | ≤ 0.05 | — |
| N | ≤ 0.05 | — |
| Hmax (sheet/strip may be lower) | ≤ 0.02 | — |
| Other, eachresiduals | ≤ 0.1 | — |
| Other, totalresiduals | ≤ 0.4 | — |
| Ti | balance | — |
Ti Grade 35-STA — frequently asked
What is Ti Grade 35-STA used for?
Ti Grade 35-STA is typically used for aerospace fasteners, formed sheet-metal brackets, superplastically formed and diffusion-bonded panels, airframe clips and stiffeners, machined fittings and links and hot-formed ducting components. In short: low-cost Ti-6Al-4V substitute; cold-formable alpha-beta alloy; lower-temperature SPF.
What is the yield strength of Ti Grade 35-STA?
Ti Grade 35-STA has a typical yield strength of 1,200 MPa (174 ksi) and a tensile strength of 1,290 MPa (187 ksi) — stronger than 100% of titanium grades. Strength varies by condition: see the 5 listed tempers.
Is Ti Grade 35-STA easy to machine?
Not especially — machinability is rated not recommended (14/100, worse than 100% of titanium grades). Machine like Ti-6Al-4V but ~10–20 % slower: rigid setups, sharp uncoated-carbide or AlTiN tools, 20–40 m/min in the annealed state, heavy flood coolant, never dwell in the cut.
Can Ti Grade 35-STA be welded?
Yes — weldability is rated good (55/100). GTAW, plasma, laser or EB welding in high-purity argon or vacuum with full back-shielding; weld metal is stronger but less ductile than base metal, so post-weld anneal or full STA is recommended.
What surface finishes work on Ti Grade 35-STA?
Descale by grit blast + HNO3/HF pickle after hot work; accepts Type II colour anodising, oxide/anodic conversion coatings for galling resistance, and polishes well due to its fine grain size.
Can Ti Grade 35-STA be formed, bent or molded?
Its main selling point — good room-temperature bendability in the ST/annealed condition and superplastic forming at only ~750–800 °C (lower than Ti-6Al-4V), enabling SPF/diffusion-bonded structures with reduced tooling wear.
What is the maximum service temperature of Ti Grade 35-STA?
Ti Grade 35-STA is rated for continuous use to about 315°C (599 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Ti Grade 35 Annealed and Ti Grade 35-STA?
Annealed is the default condition — standard stocked condition for sheet, plate and bar; best balance of strength, ductility and toughness. STA: choose for maximum strength in fasteners, springs and thin high-load sections; ductility and toughness drop. Yield strength is 920 MPa in Annealed versus 1,200 MPa in STA.
Sources
- ASTM B265 — Titanium and Titanium Alloy Strip, Sheet, and Plate (Grade 35, UNS R56340) — ASTM International (2020)
- ASTM B348 — Titanium and Titanium Alloy Bars and Billets — ASTM International (2021)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- Materials Properties Handbook: Titanium Alloys — ASM International (1994)
- SP-700 (Ti-4.5Al-3V-2Mo-2Fe) alloy data sheet — NKK / Nippon Steel & Sumitomo Metal (2015)
- ASM Handbook Vol.13B — Corrosion: Materials (titanium and titanium alloys) — ASM International (2005)
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.