Titanium Ti-15-3 · heat-treated state
Titanium Ti-15-3-STA
Properties of the STA condition, compared with the other Ti-15-3 tempers.
Age at 480–540 °C for 8–24 h once forming and welding are complete to reach 1240 MPa yield for fasteners, springs and load-bearing parts; elongation falls to 7% and machining gets harder.
What is Ti-15-3-STA?
Ti-15-3-STA is Ti-15-3 heat treated to STA — age at 480–540 °C for 8–24 h once forming and welding are complete to reach 1240 MPa yield for fasteners, springs and load-bearing parts; elongation falls to 7% and machining gets harder. Ti-15-3-STA has a yield strength of 1,240 MPa (180 ksi) and a tensile strength of 1,300 MPa (189 ksi) — stronger than 100% of titanium grades. Elongation at break is 7% and the elastic modulus is 103 GPa (14.9 Msi). Ti-15-3-STA has a density of 4.76 g/cm³ (0.172 lb/in³), heavier than 92% of titanium grades. It melts at 1,600°C (2,912 °F). O is the default condition FabDigit quotes; STA is available on request or by drawing note.
Advantages
- High strength — 1,240 MPa (180 ksi), better than 100% of titanium grades
Limitations
- Limited ductility — 7%, worse than 100% of titanium grades
- Difficult to machine — 14/100, worse than 100% of titanium grades
- Low fracture toughness — 45 MPa·√m (41 ksi·√in), worse than 98% of titanium grades
- High embodied carbon — 48 kg CO₂/kg, worse than 95% of titanium grades
- Difficult to weld — 40/100, worse than 94% of titanium grades
Ti-15-3-STA properties
Typical room-temperature values for Ti-15-3-STA — 14 properties are specific to this condition; the rest are grade-level values shared by every Ti-15-3 temper. Each bar shows where the value sits among the titanium grades in FabDigit's library — further right is higher.
Physical3
Ti-15-3-STA has a density of 4.76 g/cm³ (0.172 lb/in³), heavier than 92% of titanium grades. It melts at 1,600°C (2,912 °F).
Mechanical15
Ti-15-3-STA has a yield strength of 1,240 MPa (180 ksi) and a tensile strength of 1,300 MPa (189 ksi) — stronger than 100% of titanium grades. Elongation at break is 7% and the elastic modulus is 103 GPa (14.9 Msi).
Thermal6
Ti-15-3-STA is rated for continuous service to 315°C (599 °F). It conducts heat at 8.1 W/m·K (4.68 BTU/hr·ft·°F), better than 52% of titanium grades. Thermal expansion is 8.5 µm/m·K (4.72 µin/in·°F).
Electrical3
Ti-15-3-STA conducts electricity at 1.2 % IACS, worse than 55% of titanium grades.
Chemical & Environmental3
Corrosion resistance is excellent (88/100), worse than 77% of titanium grades.
Sustainability4
Producing a kilogram of Ti-15-3-STA takes about 750 MJ of energy and emits 48 kg of CO₂ — more than 95% of titanium grades. Typical recycled content is 20%.
Manufacturability7
Ti-15-3-STA's machinability is not recommended (14/100, worse than 100% of titanium grades); weldability fair (40/100); formability poor (20/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other Ti-15-3 tempers and conditions
Ti-15-3 is also supplied in 3 other conditions. The full side-by-side table is on the Ti-15-3 overview.
- ODefaultSolution treated at about 790–815 °C and air or water quenched, this soft single-phase beta state is the delivery condition for cold rolling, deep drawing, roll forming and welding, with ageing done afterwards.790 MPa yield · 27 HRC
- CRACombine cold rolling with a 480–540 °C age for the highest strength, 1380 MPa yield, in thin-section springs, washers and clamps; elongation is only 4% and further forming is not practical.1,380 MPa yield · 46 HRC
- STAAge at 480–540 °C for 8–24 h once forming and welding are complete to reach 1240 MPa yield for fasteners, springs and load-bearing parts; elongation falls to 7% and machining gets harder.1,240 MPa yield · 43 HRC
Working with Ti-15-3-STA
Is Ti-15-3 easy to machine?
Machinability is poor: use low surface speed with heavy feed, rigid workholding, sharp carbide or coated carbide tooling and high-pressure flood coolant. The aged condition is harder still, so avoid dwelling in the cut, which work-hardens the surface and promotes built-up edge.
Can Ti-15-3 be welded?
Weld in the solution-treated condition by GTAW, plasma arc or electron beam under inert gas or vacuum, then solution treat or age the assembly to restore joint properties. Oil, grease and air contamination must be excluded completely.
Can Ti-15-3 be formed, bent or molded?
Cold formability is excellent in the solution-treated condition — room-temperature deep drawing, roll forming and cold rolling to foil are all practical. Age after forming; do not bend material that has already been aged.
What surface finishes work on Ti-15-3?
Shot peening, HNO3/HF pickling for descaling, colour anodizing and painting all work. Conventional electroplating is not suitable; for fretting wear use ion nitriding or solid-film lubricant coatings.
Ti-15-3 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 |
|---|---|---|
| Vβ-stabilizing element | 14 – 16 | 15 |
| Cr | 2.5 – 3.5 | 3 |
| Alα-stabilizer, age-hardening | 2.5 – 3.5 | 3 |
| Sn | 2.5 – 3.5 | 3 |
| Fe | ≤ 0.25 | 0.1 |
| O | ≤ 0.13 | 0.1 |
| C | ≤ 0.05 | — |
| N | ≤ 0.05 | — |
| Hsheet/strip product | ≤ 0.02 | — |
| Ti | balance | — |
Ti-15-3-STA — frequently asked
What is Ti-15-3-STA used for?
Ti-15-3-STA is typically used for aerospace springs, fasteners and golf shafts. In short: cold-formable β titanium.
What is the yield strength of Ti-15-3-STA?
Ti-15-3-STA has a typical yield strength of 1,240 MPa (180 ksi) and a tensile strength of 1,300 MPa (189 ksi) — stronger than 100% of titanium grades. Strength varies by condition: see the 4 listed tempers.
Is Ti-15-3-STA easy to machine?
Not especially — machinability is rated not recommended (14/100, worse than 100% of titanium grades). Machinability is poor: use low surface speed with heavy feed, rigid workholding, sharp carbide or coated carbide tooling and high-pressure flood coolant. The aged condition is harder still, so avoid dwelling in the cut, which work-hardens the surface and promotes built-up edge.
Can Ti-15-3-STA be welded?
With care — weldability is rated fair (40/100). Weld in the solution-treated condition by GTAW, plasma arc or electron beam under inert gas or vacuum, then solution treat or age the assembly to restore joint properties. Oil, grease and air contamination must be excluded completely.
What surface finishes work on Ti-15-3-STA?
Shot peening, HNO3/HF pickling for descaling, colour anodizing and painting all work. Conventional electroplating is not suitable; for fretting wear use ion nitriding or solid-film lubricant coatings.
Can Ti-15-3-STA be formed, bent or molded?
Cold formability is excellent in the solution-treated condition — room-temperature deep drawing, roll forming and cold rolling to foil are all practical. Age after forming; do not bend material that has already been aged.
What is the maximum service temperature of Ti-15-3-STA?
Ti-15-3-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-15-3-O and Ti-15-3-CRA?
O is the default condition — solution treated at about 790–815 °C and air or water quenched, this soft single-phase beta state is the delivery condition for cold rolling, deep drawing, roll forming and welding, with ageing done afterwards. CRA: combine cold rolling with a 480–540 °C age for the highest strength, 1380 MPa yield, in thin-section springs, washers and clamps; elongation is only 4% and further forming is not practical. Yield strength is 790 MPa in O versus 1,380 MPa in CRA.
Can FabDigit make parts in Ti-15-3-STA?
Yes — Ti-15-3-STA is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- AMS 4914 — Titanium Alloy Sheet, Strip and Plate 15V-3Cr-3Al-3Sn, Solution Heat Treated — SAE International (2018)
- Materials Properties Handbook: Titanium Alloys — ASM International (1994)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials — 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.