Refractory Metal Ta-2.5W
UNS R05252 · ASTM B365 · also Tantalum-Tungsten
Ta-2.5W is tantalum solid-solution strengthened with tungsten (UNS R05252, ASTM B365), normally electron-beam melted and supplied as sheet, plate, rod, wire and tubing.
Reference datasheet — Ta-2.5W 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 Vacuum Annealed condition
Ta-2.5W tempers and conditions
Ta-2.5W is supplied in 4 conditions, soft to hard. Vacuum Annealed 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 |
|---|---|---|---|---|---|---|
EB Melted Ingot / As-Cast | Primary electron-beam melted ingot or sputtering-target blank stock, prior to breakdown forging/rolling; coarse grain and low strength. | 240 | 340 | 30 | 100 HB | 10 % IACS |
Vacuum AnnealedDefault fully recrystallized (default mill condition) | Standard supply condition for sheet, plate, rod and tube where maximum ductility, deep-drawability and weldability are required. | 310 | 415 | 28 | 115 HB | 9.9 % IACS |
partially recovered, not recrystallized | Choose when dimensional stability and higher strength are needed but some residual cold-work ductility must be kept, e.g. formed diaphragms and rupture discs. | 440 | 520 | 15 | 160 HB | 9.6 % IACS |
as-rolled / as-drawn hard temper | Highest strength and springback; used for hard sheet, foil, fasteners and wire where no further forming or welding is planned. | 620 | 690 | 5 | 20 HRC | 9.4 % IACS |
Supply forms, finishes and certifications
Ways Ta-2.5W is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
Cold Drawn Wire | Heavily drawn filament/wire condition | Supply form |
What is Ta-2.5W?
Ta-2.5W is tantalum solid-solution strengthened with tungsten (UNS R05252, ASTM B365), normally electron-beam melted and supplied as sheet, plate, rod, wire and tubing. It offers 310 MPa yield, 415 MPa tensile and 28 % elongation annealed — well above unalloyed tantalum — while keeping the corrosion resistance and cold formability needed for deep drawing and spinning of vessel and heat-exchanger parts. Air service is limited to about 300 °C by oxidation and interstitial embrittlement, machining is very difficult, and cost is high. Use pure Ta where the extra strength is not needed. Ta-2.5W has a density of 16.7 g/cm³ (0.603 lb/in³), heavier than 87% of refractory metal grades. It melts at 3,030°C (5,486 °F). Ta-2.5W has a yield strength of 310 MPa (45 ksi) and a tensile strength of 415 MPa (60.2 ksi) — weaker than 55% of refractory metal grades. Elongation at break is 28% and the elastic modulus is 200 GPa (29 Msi).
What is Ta-2.5W used for?
- Chemical reactor liners and cladding
- Shell-and-tube heat exchangers
- Rupture discs and bursting diaphragms
- Thermowells and immersion heater sheaths
- Acid-service valve and pump components
- Furnace heat shields and support structures
- Deep-drawn crucibles and cups
Advantages
- Good corrosion resistance — 97/100, better than 97% of refractory metal grades
- Polishes to a fine finish — 80/100, better than 97% of refractory metal grades
- Readily welded — 80/100, better than 92% of refractory metal grades
- Forms and bends easily — 85/100, better than 87% of refractory metal grades
- Ductile — tolerates forming and impact — 28%, better than 80% of refractory metal grades
Limitations
- Limited service temperature — 300°C (572 °F), worse than 95% of refractory metal grades
- High embodied carbon — 260 kg CO₂/kg, worse than 92% of refractory metal grades
- Heavy — 16.7 g/cm³ (0.603 lb/in³), worse than 87% of refractory metal grades
- Difficult to machine — 18/100, worse than 80% of refractory metal grades
Ta-2.5W properties
Typical room-temperature values for Ta-2.5W-Vacuum Annealed; bars are the position among refractory metal grades.
Physical3
Ta-2.5W has a density of 16.7 g/cm³ (0.603 lb/in³), heavier than 87% of refractory metal grades. It melts at 3,030°C (5,486 °F).
Mechanical14
Ta-2.5W has a yield strength of 310 MPa (45 ksi) and a tensile strength of 415 MPa (60.2 ksi) — weaker than 55% of refractory metal grades. Elongation at break is 28% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
Ta-2.5W is rated for continuous service to 300°C (572 °F). It conducts heat at 54 W/m·K (31.2 BTU/hr·ft·°F), better than 66% of refractory metal grades. Thermal expansion is 6.5 µm/m·K (3.61 µin/in·°F).
Electrical3
Ta-2.5W conducts electricity at 9.9 % IACS, better than 64% of refractory metal grades.
Chemical & Environmental3
Corrosion resistance is excellent (97/100), better than 97% of refractory metal grades.
Sustainability3
Producing a kilogram of Ta-2.5W takes about 4,400 MJ of energy and emits 260 kg of CO₂ — more than 94% of refractory metal grades. Typical recycled content is 20%.
Manufacturability8
Ta-2.5W's machinability is poor (18/100, worse than 80% of refractory metal grades); weldability very good (80/100); formability excellent (85/100).
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 refractory metal family
Yield strength against density for every refractory metal grade FabDigit runs. Ta-2.5W is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Ta-2.5W
Is Ta-2.5W easy to machine?
Very gummy and galling — use sharp positive-rake carbide, heavy flood of chlorinated or emulsion coolant, slow speeds (15–30 m/min) and generous feeds to avoid rubbing and smearing.
Can Ta-2.5W be welded?
GTAW in a high-purity argon glove box, or electron-beam/laser welding in vacuum; any O/N/H pickup above ~300 °C embrittles the weld, so trailing shields and clean surfaces are mandatory.
Can Ta-2.5W be formed, bent or molded?
Excellent cold formability — deep drawing, spinning and bending to tight radii are routine in the annealed condition; use lubricants and non-steel tooling inserts to avoid galling and iron pickup.
Ta-2.5W 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 |
|---|---|---|
| Wsolid-solution strengthener | 2 – 3.5 | 2.5 |
| Nb | ≤ 0.1 | |
| Mo | ≤ 0.02 | |
| Ti | ≤ 0.01 | |
| Fe | ≤ 0.01 | |
| Ni | ≤ 0.01 | |
| Si | ≤ 0.01 | |
| C | ≤ 0.01 | |
| O | ≤ 0.02 | |
| N | ≤ 0.01 | |
| H | ≤ 0 | |
| Ta | balance |
What surface finishes work on Ta-2.5W?
Pickle in HF/HNO3 mixtures to remove oxide and iron smear, then vacuum anneal; electropolishing or anodic Ta2O5 films give clean, stable surfaces for chemical or implant service.
Equivalent designations
Standards and trade names that resolve to Refractory Metal Ta-2.5W in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- R05252
- ASTM
- B365
- Trade names
- Tantalum-Tungsten
How much does Ta-2.5W cost?
Ta-2.5W is a specialty-cost refractory metal ($$$$$), pricier than about 100% 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.
Ta-2.5W — frequently asked
What is Ta-2.5W used for?
Ta-2.5W is typically used for chemical reactor liners and cladding, shell-and-tube heat exchangers, rupture discs and bursting diaphragms, thermowells and immersion heater sheaths, acid-service valve and pump components and furnace heat shields and support structures. In short: strengthened tantalum alloy.
What is the yield strength of Ta-2.5W?
Ta-2.5W has a typical yield strength of 310 MPa (45 ksi) and a tensile strength of 415 MPa (60.2 ksi) — weaker than 55% of refractory metal grades. Strength varies by condition: see the 4 listed tempers.
Is Ta-2.5W easy to machine?
Not especially — machinability is rated poor (18/100, worse than 80% of refractory metal grades). Very gummy and galling — use sharp positive-rake carbide, heavy flood of chlorinated or emulsion coolant, slow speeds (15–30 m/min) and generous feeds to avoid rubbing and smearing.
Can Ta-2.5W be welded?
Yes — weldability is rated very good (80/100). GTAW in a high-purity argon glove box, or electron-beam/laser welding in vacuum; any O/N/H pickup above ~300 °C embrittles the weld, so trailing shields and clean surfaces are mandatory.
What surface finishes work on Ta-2.5W?
Pickle in HF/HNO3 mixtures to remove oxide and iron smear, then vacuum anneal; electropolishing or anodic Ta2O5 films give clean, stable surfaces for chemical or implant service.
Can Ta-2.5W be formed, bent or molded?
Excellent cold formability — deep drawing, spinning and bending to tight radii are routine in the annealed condition; use lubricants and non-steel tooling inserts to avoid galling and iron pickup.
What is the maximum service temperature of Ta-2.5W?
Ta-2.5W is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Ta-2.5W cost?
Ta-2.5W is a specialty-cost refractory metal ($$$$$), pricier than about 100% 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 B708 — Tantalum and Tantalum Alloy Plate, Sheet and Strip — ASTM International (2021)
- ASTM B365 — Tantalum and Tantalum Alloy Rod and Wire — ASTM International (2018)
- ASTM B521 — Tantalum and Tantalum Alloy Seamless and Welded Tubes — ASTM International (2018)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (refractory metals) — ASM International (1990)
- Tantalum and tantalum alloys product data — Plansee / H.C. Starck Solutions (2022)
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.