Refractory Metal R05400-CW (Cold worked)
Supply condition
UNS R05400 · ASTM B365
Pick when higher strength and stiffness of thin foil, wire or springs matters more than formability.
Values for the CW condition
Other R05400 tempers and conditions
R05400 is listed in 3 conditions; see the grade overview at R05400.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
ODefault Annealed | Default stocked condition: maximum ductility for deep drawing, spinning and lining fabrication. | 170 | 250 | 35 | 90 HB | 12.8 % IACS |
Stress relieved | Intermediate condition: relieves cold-work stresses and improves dimensional stability while retaining much of the cold-worked strength. | 310 | 400 | 15 | 140 HB | 12.5 % IACS |
CWThis page Cold worked | Pick when higher strength and stiffness of thin foil, wire or springs matters more than formability. | 480 | 550 | 5 | 185 HB | 12.1 % IACS |
What is R05400-CW?
R05400-CW is R05400 supplied in the CW condition — pick when higher strength and stiffness of thin foil, wire or springs matters more than formability. R05400-CW has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 550 MPa (79.8 ksi) — stronger than 72% of refractory metal grades. Elongation at break is 5% and the elastic modulus is 186 GPa (27 Msi). R05400-CW has a density of 16.6 g/cm³ (0.6 lb/in³), heavier than 84% of refractory metal grades. It melts at 3,017°C (5,463 °F). O is the default condition FabDigit quotes; CW is available on request or by drawing note.
Advantages
- Tough — resists crack growth — 100 MPa·√m (91 ksi·√in), better than 98% of refractory metal grades
- Good corrosion resistance — 97/100, better than 97% of refractory metal grades
Limitations
- Limited service temperature — 250°C (482 °F), worse than 100% of refractory metal grades
- High embodied carbon — 250 kg CO₂/kg, worse than 89% of refractory metal grades
- Heavy — 16.6 g/cm³ (0.6 lb/in³), worse than 84% of refractory metal grades
- Limited ductility — 5%, worse than 78% of refractory metal grades
R05400-CW properties
Typical room-temperature values for R05400-CW; 17 are specific to this condition. Other listed values are R05400 reference data and may not represent this condition. Bars are the position among refractory metal grades.
Physical3
R05400-CW has a density of 16.6 g/cm³ (0.6 lb/in³), heavier than 84% of refractory metal grades. It melts at 3,017°C (5,463 °F).
Mechanical14
R05400-CW has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 550 MPa (79.8 ksi) — stronger than 72% of refractory metal grades. Elongation at break is 5% and the elastic modulus is 186 GPa (27 Msi).
Thermal6
R05400-CW is rated for continuous service to 250°C (482 °F). It conducts heat at 55 W/m·K (31.8 BTU/hr·ft·°F), better than 67% of refractory metal grades. Thermal expansion is 6.5 µm/m·K (3.61 µin/in·°F).
Electrical3
R05400-CW conducts electricity at 12.1 % IACS, better than 68% of refractory metal grades.
Chemical & Environmental3
Corrosion resistance is excellent (97/100), better than 97% of refractory metal grades.
Sustainability4
Producing a kilogram of R05400-CW takes about 4,000 MJ of energy and emits 250 kg of CO₂ — more than 89% of refractory metal grades. Typical recycled content is 30%.
Manufacturability8
R05400-CW's machinability is poor (32/100, better than 67% of refractory metal grades); weldability very good (70/100); formability good (55/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with R05400-CW
Is R05400 easy to machine?
Very gummy and galling-prone — use sharp, highly positive-rake carbide or HSS tools, heavy chlorinated or sulfurized coolant, slow speeds (15–30 m/min) and generous feeds to avoid rubbing; never let the tool dwell.
Can R05400 be welded?
GTAW in a high-purity argon glovebox, EB or laser welding only; any pickup of O₂, N₂ or H₂ during welding causes severe embrittlement, and Ta must not be welded to Fe/Ni alloys directly.
Can R05400 be formed, bent or molded?
Outstanding cold formability — deep draws, spinning and >90 % cold rolling are routine with clean tooling and non-galling lubricants; vacuum anneal at 1100–1300 °C to restore ductility between severe operations.
What surface finishes work on R05400?
Chemically clean/pickle in HF–HNO₃ then electropolish; anodizing in dilute phosphoric or citric electrolyte builds a controlled Ta₂O₅ film for dielectric or colored finishes; avoid abrasive smearing.
R05400 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 |
|---|---|---|
| Nbcolumbium | ≤ 0.1 | 0.03 |
| W | ≤ 0.05 | 0.01 |
| Mo | ≤ 0.02 | 0.01 |
| Ti | ≤ 0.01 | 0 |
| Fe | ≤ 0.01 | 0 |
| Ni | ≤ 0.01 | 0 |
| Si | ≤ 0.01 | 0 |
| C | ≤ 0.01 | 0 |
| Ohigher than EB-melted R05200 (0.015 max) because of powder-metallurgy route | ≤ 0.03 | 0.02 |
| N | ≤ 0.01 | 0 |
| H | ≤ 0 | 5×10⁻⁴ |
| Ta99.9 % min (Ta+Nb basis per ASTM B365/B708 Type 2) | balance | — |
R05400-CW — frequently asked
What is R05400-CW used for?
R05400-CW is typically used for capacitor anode powder feedstock, sputtering target blanks, mill product starting stock and electronic grade tantalum components. In short: baseline unalloyed tantalum; near-inert to acids; deep-draw capable.
What is the yield strength of R05400-CW?
R05400-CW has a typical yield strength of 480 MPa (69.6 ksi) and a tensile strength of 550 MPa (79.8 ksi) — stronger than 72% of refractory metal grades. Strength varies by condition: see the 3 listed tempers.
Is R05400-CW easy to machine?
Not especially — machinability is rated poor (32/100, better than 67% of refractory metal grades). Very gummy and galling-prone — use sharp, highly positive-rake carbide or HSS tools, heavy chlorinated or sulfurized coolant, slow speeds (15–30 m/min) and generous feeds to avoid rubbing; never let the tool dwell.
Can R05400-CW be welded?
Yes — weldability is rated very good (70/100). GTAW in a high-purity argon glovebox, EB or laser welding only; any pickup of O₂, N₂ or H₂ during welding causes severe embrittlement, and Ta must not be welded to Fe/Ni alloys directly.
What surface finishes work on R05400-CW?
Chemically clean/pickle in HF–HNO₃ then electropolish; anodizing in dilute phosphoric or citric electrolyte builds a controlled Ta₂O₅ film for dielectric or colored finishes; avoid abrasive smearing.
Can R05400-CW be formed, bent or molded?
Outstanding cold formability — deep draws, spinning and >90 % cold rolling are routine with clean tooling and non-galling lubricants; vacuum anneal at 1100–1300 °C to restore ductility between severe operations.
What is the maximum service temperature of R05400-CW?
R05400-CW is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between R05400-O and R05400-CW?
O is the default condition — default stocked condition: maximum ductility for deep drawing, spinning and lining fabrication. CW: pick when higher strength and stiffness of thin foil, wire or springs matters more than formability. Yield strength is 170 MPa in O versus 480 MPa in CW.
Sources
- ASTM B365 — Tantalum and Tantalum Alloy Rod and Wire — ASTM International (2018)
- ASTM B708 — Tantalum and Tantalum Alloy Plate, Sheet and Strip — ASTM International (2021)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (refractory metals) — ASM International (1990)
- CRC Handbook of Chemistry and Physics — physical properties of tantalum — CRC Press (2023)
- Tantalum mill product data (sheet, rod, wire) — Global Advanced Metals / H.C. Starck Solutions (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.