Titanium Ti-15Mo-2.7Nb-3Al-0.2Si
UNS R58210
Ti-15Mo-2.7Nb-3Al-0.2Si (UNS R58210) is an oxidation-resistant metastable beta titanium alloy developed for elevated-temperature service and as a matrix for titanium metal-matrix composites.
Reference datasheet — Ti-15Mo-2.7Nb-3Al-0.2Si is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the ST condition
Ti-15Mo-2.7Nb-3Al-0.2Si tempers and conditions
Ti-15Mo-2.7Nb-3Al-0.2Si is supplied in 4 conditions, soft to hard. ST is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
STDefault Solution annealed | Standard as-supplied condition for sheet, foil and bar: soft, ductile, cold-formable and weldable, aged after fabrication if strength is required. | 810 | 840 | 18 | 28 HRC | — |
Cold rolled | Cold-rolled thin strip and MMC matrix foil (0.1–0.3 mm) supplied work-hardened; solution treat or age after lay-up/consolidation. | 950 | 1,000 | 8 | 33 HRC | 1.3 % IACS |
STA 595 °C | Choose when thermal stability up to ~600 °C, creep resistance and better ductility/toughness matter more than peak tensile strength. | 1,050 | 1,140 | 9 | 37 HRC | — |
STA 538 °C | Pick for maximum room- and elevated-temperature strength in airframe/engine parts once forming and welding are complete. | 1,210 | 1,310 | 6 | 41 HRC | — |
What is Ti-15Mo-2.7Nb-3Al-0.2Si?
Ti-15Mo-2.7Nb-3Al-0.2Si (UNS R58210) is an oxidation-resistant metastable beta titanium alloy developed for elevated-temperature service and as a matrix for titanium metal-matrix composites. It offers 810 MPa yield, 840 MPa tensile, 18% elongation, 28 HRC and an 80 GPa modulus, with a maximum service temperature of 480 °C, and it cold-rolls to thin foil in the solution-treated condition (formability 75). Machinability is low (20) and thermal conductivity is only 7.6 W/m·K, so cutting is slow. Ti-3Al-8V-6Cr-4Mo-4Zr is the usual alternative when 480 °C capability is not needed. Ti-15Mo-2.7Nb-3Al-0.2Si has a density of 4.94 g/cm³ (0.178 lb/in³), heavier than 97% of titanium grades. It melts at 1,600°C (2,912 °F). Ti-15Mo-2.7Nb-3Al-0.2Si has a yield strength of 810 MPa (117 ksi) and a tensile strength of 840 MPa (122 ksi) — stronger than 59% of titanium grades. Elongation at break is 18% and the elastic modulus is 80 GPa (11.6 Msi).
What is Ti-15Mo-2.7Nb-3Al-0.2Si used for?
- exhaust system components
- MMC matrix
- high-temperature airframe parts
Advantages
- High service temperature — 480°C (896 °F), better than 90% of titanium grades
- Forms and bends easily — 75/100, better than 83% of titanium grades
Limitations
- Low stiffness — 80 GPa (11.6 Msi), worse than 97% of titanium grades
- Difficult to weld — 60/100, worse than 83% of titanium grades
Ti-15Mo-2.7Nb-3Al-0.2Si properties
Typical room-temperature values for Ti-15Mo-2.7Nb-3Al-0.2Si-ST; bars are the position among titanium grades.
Physical3
Ti-15Mo-2.7Nb-3Al-0.2Si has a density of 4.94 g/cm³ (0.178 lb/in³), heavier than 97% of titanium grades. It melts at 1,600°C (2,912 °F).
Mechanical14
Ti-15Mo-2.7Nb-3Al-0.2Si has a yield strength of 810 MPa (117 ksi) and a tensile strength of 840 MPa (122 ksi) — stronger than 59% of titanium grades. Elongation at break is 18% and the elastic modulus is 80 GPa (11.6 Msi).
Thermal6
Ti-15Mo-2.7Nb-3Al-0.2Si is rated for continuous service to 480°C (896 °F). It conducts heat at 7.6 W/m·K (4.39 BTU/hr·ft·°F), worse than 59% of titanium grades. Thermal expansion is 7.7 µm/m·K (4.28 µin/in·°F).
Electrical3
Ti-15Mo-2.7Nb-3Al-0.2Si conducts electricity at 1.3 % IACS, worse than 51% of titanium grades.
Chemical & Environmental3
Corrosion resistance is excellent (92/100), better than 53% of titanium grades.
Sustainability4
Producing a kilogram of Ti-15Mo-2.7Nb-3Al-0.2Si takes about 700 MJ of energy and emits 42 kg of CO₂ — more than 74% of titanium grades. Typical recycled content is 15%.
Manufacturability8
Ti-15Mo-2.7Nb-3Al-0.2Si's machinability is poor (20/100, worse than 68% of titanium grades); weldability good (60/100); formability very good (75/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the titanium family
Yield strength against density for every titanium grade FabDigit runs. Ti-15Mo-2.7Nb-3Al-0.2Si is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Ti-15Mo-2.7Nb-3Al-0.2Si
Is Ti-15Mo-2.7Nb-3Al-0.2Si easy to machine?
Machine like a tough β-Ti alloy: rigid setups, sharp uncoated carbide or PVD-coated tools, low surface speed (15–30 m/min aged), heavy positive rake, generous flood coolant to counter the 7.6 W/m·K conductivity; avoid dwelling and rubbing which work-hardens the surface.
Can Ti-15Mo-2.7Nb-3Al-0.2Si be welded?
GTAW, plasma and EB/laser welding are practical in the solution-treated condition with full inert-gas or vacuum shielding; welds age-harden with the parent but ductility drops, so post-weld solution treat + age (or age only) and avoid welding fully aged material.
Can Ti-15Mo-2.7Nb-3Al-0.2Si be formed, bent or molded?
Excellent cold formability for a high-strength Ti alloy in the ST condition — cold rollable to thin foil, brake-formable with generous radii and ~2–3× springback allowance; hot form/superplastically form 700–815 °C, then age.
Ti-15Mo-2.7Nb-3Al-0.2Si 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 |
|---|---|---|
| Moβ stabilizer, oxidation/acid resistance | 14 – 16 | 15 |
| Nb | 2.2 – 3.2 | 2.7 |
| Al | 2.5 – 3.5 | 3 |
| Sicreep and oxidation resistance | 0.15 – 0.25 | 0.2 |
| Fe | ≤ 0.4 | |
| O | ≤ 0.17 | |
| C | ≤ 0.05 | |
| N | ≤ 0.05 | |
| Hmax, sheet/strip | ≤ 0.02 | |
| Y | ≤ 0.01 | |
| Other, eachresidual elements, 0.40 max total | ≤ 0.1 | |
| Ti | balance |
What surface finishes work on Ti-15Mo-2.7Nb-3Al-0.2Si?
Pickle in HNO3/HF after hot work to remove alpha case; Ti anodize (AMS 2488) or oxide/MoS2 coatings for galling control; grit blast + primer for painting; takes a good mechanical polish but is prone to galling against itself, so use dry-film lube or plating on threads.
Surface treatments FabDigit runs on titanium parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Titanium Ti-15Mo-2.7Nb-3Al-0.2Si in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- R58210
- Also called
- Beta 21S
How much does Ti-15Mo-2.7Nb-3Al-0.2Si cost?
Ti-15Mo-2.7Nb-3Al-0.2Si is a high-cost titanium ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Ti-15Mo-2.7Nb-3Al-0.2Si — frequently asked
What is Ti-15Mo-2.7Nb-3Al-0.2Si used for?
Ti-15Mo-2.7Nb-3Al-0.2Si is typically used for exhaust system components, MMC matrix and high-temperature airframe parts. In short: most oxidation-resistant beta Ti; 480 °C service capability; cold-rollable to foil.
What is the yield strength of Ti-15Mo-2.7Nb-3Al-0.2Si?
Ti-15Mo-2.7Nb-3Al-0.2Si has a typical yield strength of 810 MPa (117 ksi) and a tensile strength of 840 MPa (122 ksi) — stronger than 59% of titanium grades. Strength varies by condition: see the 4 listed tempers.
Is Ti-15Mo-2.7Nb-3Al-0.2Si easy to machine?
Not especially — machinability is rated poor (20/100, worse than 68% of titanium grades). Machine like a tough β-Ti alloy: rigid setups, sharp uncoated carbide or PVD-coated tools, low surface speed (15–30 m/min aged), heavy positive rake, generous flood coolant to counter the 7.6 W/m·K conductivity; avoid dwelling and rubbing which work-hardens the surface.
Can Ti-15Mo-2.7Nb-3Al-0.2Si be welded?
Yes — weldability is rated good (60/100). GTAW, plasma and EB/laser welding are practical in the solution-treated condition with full inert-gas or vacuum shielding; welds age-harden with the parent but ductility drops, so post-weld solution treat + age (or age only) and avoid welding fully aged material.
What surface finishes work on Ti-15Mo-2.7Nb-3Al-0.2Si?
Pickle in HNO3/HF after hot work to remove alpha case; Ti anodize (AMS 2488) or oxide/MoS2 coatings for galling control; grit blast + primer for painting; takes a good mechanical polish but is prone to galling against itself, so use dry-film lube or plating on threads.
Can Ti-15Mo-2.7Nb-3Al-0.2Si be formed, bent or molded?
Excellent cold formability for a high-strength Ti alloy in the ST condition — cold rollable to thin foil, brake-formable with generous radii and ~2–3× springback allowance; hot form/superplastically form 700–815 °C, then age.
What is the maximum service temperature of Ti-15Mo-2.7Nb-3Al-0.2Si?
Ti-15Mo-2.7Nb-3Al-0.2Si is rated for continuous use to about 480°C (896 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Ti-15Mo-2.7Nb-3Al-0.2Si-ST and Ti-15Mo-2.7Nb-3Al-0.2Si STA-538?
ST is the default condition — standard as-supplied condition for sheet, foil and bar: soft, ductile, cold-formable and weldable, aged after fabrication if strength is required. STA-538: pick for maximum room- and elevated-temperature strength in airframe/engine parts once forming and welding are complete. Yield strength is 810 MPa in ST versus 1,210 MPa in STA-538.
How much does Ti-15Mo-2.7Nb-3Al-0.2Si cost?
Ti-15Mo-2.7Nb-3Al-0.2Si is a high-cost titanium ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM B265 / B348 — Titanium Grade 21 (UNS R58210) — ASTM International (2020)
- TIMETAL 21S (Beta 21S) alloy data sheet — TIMET (2000)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- Materials Properties Handbook: Titanium Alloys — ASM International (1994)
- MMPDS / MIL-HDBK-5 titanium alloy chapters (typical values) — Battelle/FAA (2021)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.