Titanium Ti-15Mo-STA (Solution treated and aged)
Heat-treated state
UNS R58150 · ASTM F2066
Choose when implant or component strength must exceed 1000 MPa and reduced ductility/toughness is acceptable.
Values for the STA condition
Other Ti-15Mo tempers and conditions
Ti-15Mo is listed in 5 conditions; see the grade overview at Ti-15Mo.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
STDefault Solution annealed | Standard stocked implant condition: single-phase beta, lowest modulus, best ductility and cold formability. | 570 | 760 | 22 | 27 HRC | — |
Mill annealed / hot worked and annealed | Plate, sheet and bar as hot worked then recrystallisation annealed; slightly higher strength than water-quenched ST because of fine α, marginally lower ductility. | 650 | 820 | 18 | 30 HRC | — |
Cold worked | Cold drawn wire, screws and small bar where high yield strength is needed without an aging cycle. | 900 | 980 | 12 | 34 HRC | 1.2 % IACS |
STAThis page Solution treated and aged | Choose when implant or component strength must exceed 1000 MPa and reduced ductility/toughness is acceptable. | 1,010 | 1,100 | 10 | 38 HRC | — |
Cold worked and aged | Highest strength route for small-section wire, pins and fixation screws; ductility drops to single digits. | 1,150 | 1,220 | 8 | 41 HRC | — |
What is Ti-15Mo-STA?
Ti-15Mo-STA is Ti-15Mo heat treated to STA — choose when implant or component strength must exceed 1000 MPa and reduced ductility/toughness is acceptable. Ti-15Mo-STA has a yield strength of 1,010 MPa (146 ksi) and a tensile strength of 1,100 MPa (160 ksi) — stronger than 93% of titanium grades. Elongation at break is 10% and the elastic modulus is 98 GPa (14.2 Msi). Ti-15Mo-STA has a density of 4.96 g/cm³ (0.179 lb/in³), heavier than 98% of titanium grades. It melts at 1,670°C (3,038 °F). ST is the default condition FabDigit quotes; STA is available on request or by drawing note.
Advantages
- Polishes to a fine finish — 80/100, better than 98% of titanium grades
- High strength — 1,010 MPa (146 ksi), better than 93% of titanium grades
Limitations
- Limited ductility — 10%, worse than 93% of titanium grades
- Low fracture toughness — 55 MPa·√m (50.1 ksi·√in), worse than 90% of titanium grades
- Difficult to weld — 50/100, worse than 89% of titanium grades
Ti-15Mo-STA properties
Typical room-temperature values for Ti-15Mo-STA; 14 are specific to this condition. Other listed values are Ti-15Mo reference data and may not represent this condition. Bars are the position among titanium grades.
Physical3
Ti-15Mo-STA has a density of 4.96 g/cm³ (0.179 lb/in³), heavier than 98% of titanium grades. It melts at 1,670°C (3,038 °F).
Mechanical15
Ti-15Mo-STA has a yield strength of 1,010 MPa (146 ksi) and a tensile strength of 1,100 MPa (160 ksi) — stronger than 93% of titanium grades. Elongation at break is 10% and the elastic modulus is 98 GPa (14.2 Msi).
Thermal6
Ti-15Mo-STA is rated for continuous service to 315°C (599 °F). It conducts heat at 8.5 W/m·K (4.91 BTU/hr·ft·°F), better than 55% of titanium grades. Thermal expansion is 8.7 µm/m·K (4.83 µin/in·°F).
Electrical3
Ti-15Mo-STA conducts electricity at 1.2 % IACS, worse than 55% of titanium grades.
Chemical & Environmental3
Corrosion resistance is excellent (93/100), better than 72% of titanium grades.
Sustainability4
Producing a kilogram of Ti-15Mo-STA takes about 700 MJ of energy and emits 45 kg of CO₂ — more than 74% of titanium grades. Typical recycled content is 5%.
Manufacturability8
Ti-15Mo-STA's machinability is poor (18/100, worse than 83% of titanium grades); weldability fair (50/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Ti-15Mo-STA
Is Ti-15Mo easy to machine?
Machine like a tough beta titanium: rigid setup, sharp uncoated-carbide or AlTiN tools, low surface speed (~20–35 m/min), heavy feed, copious flood coolant and no dwelling — work hardening and galling are worse than Ti-6Al-4V.
Can Ti-15Mo be welded?
GTAW/PAW/EBW/laser weld readily in inert gas or vacuum with matching filler; beta phase keeps welds ductile as-welded, but avoid contamination pickup and re-solution treat if aging is planned.
Can Ti-15Mo be formed, bent or molded?
In the solution-treated beta condition it is the most cold-formable titanium class — bending, deep drawing and wire drawing are practical; hot working above the ~750 °C beta transus for forging, then solution treat before final forming.
What surface finishes work on Ti-15Mo?
Polishes to implant-quality finish; passivates spontaneously and can be nitric-acid passivated, colour-anodised for part identification, chemically etched/blasted, or given hydroxyapatite/anodic bio-surfaces.
Ti-15Mo 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 |
|---|---|---|
| Mobeta stabiliser | 14 – 16 | 15 |
| Fe | ≤ 0.1 | 0.03 |
| Ointerstitial, controls strength | ≤ 0.2 | 0.12 |
| C | ≤ 0.1 | 0.02 |
| N | ≤ 0.05 | 0.01 |
| H | ≤ 0.02 | 0.01 |
| Other, eachresidual elements | ≤ 0.1 | — |
| Other, totalresidual elements total | ≤ 0.4 | — |
| Ti | balance | — |
Ti-15Mo-STA — frequently asked
What is Ti-15Mo-STA used for?
Ti-15Mo-STA is typically used for surgical implants, dental devices and biomedical fasteners. In short: lowest-modulus implant titanium; most cold-formable titanium class; aluminum- and vanadium-free.
What is the yield strength of Ti-15Mo-STA?
Ti-15Mo-STA has a typical yield strength of 1,010 MPa (146 ksi) and a tensile strength of 1,100 MPa (160 ksi) — stronger than 93% of titanium grades. Strength varies by condition: see the 5 listed tempers.
Is Ti-15Mo-STA easy to machine?
Not especially — machinability is rated poor (18/100, worse than 83% of titanium grades). Machine like a tough beta titanium: rigid setup, sharp uncoated-carbide or AlTiN tools, low surface speed (~20–35 m/min), heavy feed, copious flood coolant and no dwelling — work hardening and galling are worse than Ti-6Al-4V.
Can Ti-15Mo-STA be welded?
With care — weldability is rated fair (50/100). GTAW/PAW/EBW/laser weld readily in inert gas or vacuum with matching filler; beta phase keeps welds ductile as-welded, but avoid contamination pickup and re-solution treat if aging is planned.
What surface finishes work on Ti-15Mo-STA?
Polishes to implant-quality finish; passivates spontaneously and can be nitric-acid passivated, colour-anodised for part identification, chemically etched/blasted, or given hydroxyapatite/anodic bio-surfaces.
Can Ti-15Mo-STA be formed, bent or molded?
In the solution-treated beta condition it is the most cold-formable titanium class — bending, deep drawing and wire drawing are practical; hot working above the ~750 °C beta transus for forging, then solution treat before final forming.
What is the maximum service temperature of Ti-15Mo-STA?
Ti-15Mo-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-15Mo-ST and Ti-15Mo-STA?
ST is the default condition — standard stocked implant condition: single-phase beta, lowest modulus, best ductility and cold formability. STA: choose when implant or component strength must exceed 1000 MPa and reduced ductility/toughness is acceptable. Yield strength is 570 MPa in ST versus 1,010 MPa in STA.
Sources
- ASTM F2066 — Standard Specification for Wrought Titanium-15 Molybdenum Alloy for Surgical Implant Applications (UNS R58150) — ASTM International (2018)
- ASM Handbook, Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- Materials Properties Handbook: Titanium Alloys — ASM International (1994)
- Medical-grade beta titanium bar and wire datasheets (Ti-15Mo) — titanium mill suppliers (2023)
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.