Titanium Grade 5 · heat-treated state
Titanium Grade 5-STA
Properties of the STA condition, compared with the other Grade 5 tempers.
Choose when maximum strength is needed in sections under ~25 mm; ductility and toughness drop.
What is Grade 5-STA?
Grade 5-STA is Grade 5 heat treated to STA — choose when maximum strength is needed in sections under ~25 mm; ductility and toughness drop. Grade 5-STA has a yield strength of 1,070 MPa (155 ksi) and a tensile strength of 1,150 MPa (167 ksi) — stronger than 98% of titanium grades. Elongation at break is 10% and the elastic modulus is 113.8 GPa (16.5 Msi). Grade 5-STA has a density of 4.43 g/cm³ (0.16 lb/in³), lighter than 89% of titanium grades. It melts at 1,604°C (2,919 °F). O is the default condition FabDigit quotes; STA is available on request or by drawing note.
Advantages
- High strength — 1,070 MPa (155 ksi), better than 98% of titanium grades
Limitations
- Limited ductility — 10%, worse than 93% of titanium grades
- Poor heat conductor — 6.7 W/m·K (3.87 BTU/hr·ft·°F), worse than 92% of titanium grades
- Low fracture toughness — 55 MPa·√m (50.1 ksi·√in), worse than 90% of titanium grades
- Low electrical conductivity — 1 % IACS, worse than 89% of titanium grades
Grade 5-STA properties
Typical room-temperature values for Grade 5-STA — 12 properties are specific to this condition; the rest are grade-level values shared by every Grade 5 temper. Each bar shows where the value sits among the titanium grades in FabDigit's library — further right is higher.
Physical3
Grade 5-STA has a density of 4.43 g/cm³ (0.16 lb/in³), lighter than 89% of titanium grades. It melts at 1,604°C (2,919 °F).
Mechanical16
Grade 5-STA has a yield strength of 1,070 MPa (155 ksi) and a tensile strength of 1,150 MPa (167 ksi) — stronger than 98% of titanium grades. Elongation at break is 10% and the elastic modulus is 113.8 GPa (16.5 Msi).
Thermal6
Grade 5-STA is rated for continuous service to 350°C (662 °F). It conducts heat at 6.7 W/m·K (3.87 BTU/hr·ft·°F), worse than 92% of titanium grades. Thermal expansion is 8.6 µm/m·K (4.78 µin/in·°F).
Electrical3
Grade 5-STA conducts electricity at 1 % IACS, worse than 89% of titanium grades.
Chemical & Environmental3
Corrosion resistance is excellent (88/100), worse than 77% of titanium grades.
Sustainability4
Producing a kilogram of Grade 5-STA takes about 650 MJ of energy and emits 42 kg of CO₂ — less than 75% of titanium grades. Typical recycled content is 25%.
Manufacturability8
Grade 5-STA's machinability is poor (17/100, worse than 89% of titanium grades); weldability very good (75/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other Grade 5 tempers and conditions
Grade 5 is also supplied in 6 other conditions. The full side-by-side table is on the Grade 5 overview.
- ODefaultDefault stocked condition for bar, plate, sheet and forgings — best balance of strength, ductility and toughness.880 MPa yield · 36 HRC
- As PrintedHighest as-built strength from the fine martensitic α' structure, but low ductility, anisotropy and high residual stress — usually stress relieved or HIPed before service.1,120 MPa yield · 40 HRC
- STAChoose when maximum strength is needed in sections under ~25 mm; ductility and toughness drop.1,070 MPa yield · 41 HRC
- HIPCloses porosity and lack-of-fusion defects in castings and printed parts, restoring wrought-like ductility and fatigue life.890 MPa yield · 34 HRC
Working with Grade 5-STA
Is Grade 5 easy to machine?
Low speed (30–60 m/min carbide), heavy positive-rake sharp tooling, rigid setup and flood high-pressure coolant; never dwell in the cut — chips are pyrophoric and work hardening plus low conductivity burns edges.
Can Grade 5 be welded?
Excellent by GTAW/EBW/laser with full inert gas or trailing-shield/chamber protection; keep O/N/H pickup low and stress relieve after — welds lose ductility if discoloured beyond light straw.
Can Grade 5 be formed, bent or molded?
Cold formability is poor (min bend radius ~4–5t, high springback); hot form 600–800 °C or use superplastic forming near 900 °C, then descale by molten-salt/acid pickle.
What surface finishes work on Grade 5?
Takes colour (Type II) and hard anodize (AMS 2488 Type III) well for anti-galling; can be shot peened for fatigue, bead blasted, polished to mirror; avoid chlorinated cleaners and cadmium/mercury contact.
Grade 5 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 |
|---|---|---|
| Alα stabilizer | 5.5 – 6.75 | 6 |
| Vβ stabilizer | 3.5 – 4.5 | 4 |
| Fe | ≤ 0.4 | 0.2 |
| O0.13 max for ELI Gr 23 | ≤ 0.2 | 0.16 |
| C | ≤ 0.08 | 0.02 |
| N | ≤ 0.05 | 0.02 |
| H0.0125 max for bar/billet per ASTM B348 | ≤ 0.02 | 0.01 |
| Ywhen specified | ≤ 0.01 | — |
| Residuals, eachtotal 0.4 max | ≤ 0.1 | — |
| Ti | balance | — |
Grade 5-STA — frequently asked
What is Grade 5-STA used for?
Grade 5-STA is typically used for aircraft turbine blades and engine hardware, medical implants and instrument bodies, airframe structural fittings and lugs, 3D-printed lattice and bracket structures, motorsport and high-load fasteners and subsea and offshore pressure housings. In short: workhorse aerospace titanium.
What is the yield strength of Grade 5-STA?
Grade 5-STA has a typical yield strength of 1,070 MPa (155 ksi) and a tensile strength of 1,150 MPa (167 ksi) — stronger than 98% of titanium grades. Strength varies by condition: see the 7 listed tempers.
Is Grade 5-STA easy to machine?
Not especially — machinability is rated poor (17/100, worse than 89% of titanium grades). Low speed (30–60 m/min carbide), heavy positive-rake sharp tooling, rigid setup and flood high-pressure coolant; never dwell in the cut — chips are pyrophoric and work hardening plus low conductivity burns edges.
Can Grade 5-STA be welded?
Yes — weldability is rated very good (75/100). Excellent by GTAW/EBW/laser with full inert gas or trailing-shield/chamber protection; keep O/N/H pickup low and stress relieve after — welds lose ductility if discoloured beyond light straw.
What surface finishes work on Grade 5-STA?
Takes colour (Type II) and hard anodize (AMS 2488 Type III) well for anti-galling; can be shot peened for fatigue, bead blasted, polished to mirror; avoid chlorinated cleaners and cadmium/mercury contact.
Can Grade 5-STA be formed, bent or molded?
Cold formability is poor (min bend radius ~4–5t, high springback); hot form 600–800 °C or use superplastic forming near 900 °C, then descale by molten-salt/acid pickle.
What is the maximum service temperature of Grade 5-STA?
Grade 5-STA is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Grade 5-O and Grade 5-STA?
O is the default condition — default stocked condition for bar, plate, sheet and forgings — best balance of strength, ductility and toughness. STA: choose when maximum strength is needed in sections under ~25 mm; ductility and toughness drop. Yield strength is 880 MPa in O versus 1,070 MPa in STA.
Can FabDigit make parts in Grade 5-STA?
Yes — Grade 5-STA is available for CNC machining, sheet metal and 3D printing with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM B348 / B265 — Titanium and Titanium Alloy Bar, Billet, Strip, Sheet and Plate — ASTM International (2021)
- AMS 4911 / AMS 4928 / AMS 4965 — Ti-6Al-4V sheet, bar, STA bar — SAE International (2020)
- ISO 5832-3 — Implants for surgery, wrought Ti-6Al-4V alloy — ISO (2021)
- GB/T 3620.1 / GB/T 2965 — (TC4) — SAC (2016)
- ASTM F2924 / F3001 — Additive manufactured Ti-6Al-4V — ASTM International (2021)
- ASM Materials Properties Handbook: Titanium Alloys — ASM International (1994)
- MMPDS-17, Chapter 5 — Titanium alloys — Battelle/FAA (2022)
- TIMETAL 6-4 technical data sheet — TIMET (2020)
- EOS Titanium Ti64 material data sheet — EOS GmbH (2022)
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.