Tungsten Alloy Pure W
also CP Tungsten
Pure W is commercially pure tungsten (99.95 % grade), the densest (19.25 g/cm³) and highest-melting machinable refractory metal, combining high elastic modulus, low thermal expansion, 165 W/m·K conductivity and high strength at temperature.
Reference datasheet — Pure W 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 As Rolled condition
Pure W tempers and conditions
Pure W is supplied in 7 conditions, soft to hard. As Rolled is the default FabDigit quotes; the values on this page are for it.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
pressed and vacuum/hydrogen sintered, ~95–98 % of theoretical density | Cheapest near-net P/M form for shielding blocks, crucibles and simple electrodes where residual porosity and low strength are acceptable. | 300 | 350 | 0.5 | 29 HRC | 26 % IACS |
laser powder-bed fusion (LPBF/SLM) or EBM pure W, as-built | For complex collimators, heat sinks and plasma-facing geometries impossible to machine; expect 96–99 % density, solidification microcracking, anisotropy and near-zero ductility — HIP or stress relief is normally added. | 320 | 350 | 0.3 | 39 HRC | 120 W/m·K |
Hot isostatic pressed | Pick for large, complex or additively made W parts needing pore-free, leak-tight, isotropic material without a wrought texture. | 380 | 480 | 1 | 33 HRC | 168 W/m·K |
heated above ~1400 °C, equiaxed grains | The state reached after high-temperature service or welding: softest and most brittle at room temperature, chosen only for parts that operate hot and dimensionally stable. | 400 | 550 | 1.5 | 33 HRC | 172 W/m·K |
wrought W annealed below recrystallization (~900–1200 °C) | Use when machining/EDM distortion or residual-stress cracking must be avoided while keeping most of the wrought strength and fine grain. | 550 | 700 | 5 | 35 HRC | 31 % IACS |
Pressed, sintered and hot-forged/upset bar, disc or block | Choose for thick bar, discs and crucible/electrode blanks where full density and more isotropic properties matter more than peak sheet strength. | 620 | 750 | 3 | 37 HRC | 165 W/m·K |
As RolledDefault pressed, sintered and warm/hot rolled sheet, plate or foil | Default stocked wrought condition for plate, sheet and foil: highest strength and hardness, fibrous texture, minimum room-temperature ductility still usable for flat parts and shielding. | 700 | 800 | 3 | 38 HRC | 165 W/m·K |
Supply forms, finishes and certifications
Ways Pure W is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
Drawn Wire | Swaged and Drawn Wire | Supply form |
What is Pure W?
Pure W is commercially pure tungsten (99.95 % grade), the densest (19.25 g/cm³) and highest-melting machinable refractory metal, combining high elastic modulus, low thermal expansion, 165 W/m·K conductivity and high strength at temperature. It is used for filaments and electrodes, X-ray and radiation shielding, plasma-facing parts and EDM electrodes, supplied as PM rolled sheet, forged or drawn bar and wire, and sintered or HIP blanks. Limits are room-temperature brittleness (3 % elongation, ductile-brittle transition above ambient when recrystallized), rapid oxidation and oxide volatilization in air above 400 °C, and shaping essentially only by grinding or EDM. Tungsten heavy alloys machine more easily at lower density. Pure W has a density of 19.25 g/cm³ (0.695 lb/in³), heavier than 76% of tungsten alloy grades. It melts at 3,422°C (6,192 °F). Pure W has a yield strength of 700 MPa (102 ksi) and a tensile strength of 800 MPa (116 ksi) — weaker than 61% of tungsten alloy grades. Elongation at break is 3% and the elastic modulus is 400 GPa (58 Msi).
What is Pure W used for?
- X-ray tube anodes
- Radiation shielding blocks and collimators
- GTAW welding electrodes
- Furnace hot-zone elements and shields
- Ion- and plasma-facing components
- EDM electrodes
- Lamp filaments
Pure W properties
Typical room-temperature values for Pure W-As Rolled; bars are the position among tungsten alloy grades.
Physical3
Pure W has a density of 19.25 g/cm³ (0.695 lb/in³), heavier than 76% of tungsten alloy grades. It melts at 3,422°C (6,192 °F).
Mechanical16
Pure W has a yield strength of 700 MPa (102 ksi) and a tensile strength of 800 MPa (116 ksi) — weaker than 61% of tungsten alloy grades. Elongation at break is 3% and the elastic modulus is 400 GPa (58 Msi).
Thermal6
Pure W is rated for continuous service to 500°C (932 °F). It conducts heat at 165 W/m·K (95.3 BTU/hr·ft·°F), better than 69% of tungsten alloy grades. Thermal expansion is 4.5 µm/m·K (2.5 µin/in·°F).
Electrical3
Pure W conducts electricity at 30 % IACS, better than 64% of tungsten alloy grades.
Chemical & Environmental3
Corrosion resistance is good (60/100), better than 50% of tungsten alloy grades.
Sustainability3
Producing a kilogram of Pure W takes about 400 MJ of energy and emits 27 kg of CO₂ — more than 74% of tungsten alloy grades. Typical recycled content is 30%.
Manufacturability8
Pure W's machinability is not recommended (8/100, worse than 71% of tungsten alloy grades); weldability not recommended (10/100); formability not recommended (5/100).
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 tungsten alloy family
Yield strength against density for every tungsten alloy grade FabDigit runs. Pure W is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Pure W
Is Pure W easy to machine?
Treat as a brittle hard metal: grinding, EDM/wire-EDM and laser cutting are preferred; if turning/milling, use rigid setups, negative-rake carbide or CBN, low speed, heavy flood coolant and preheat 200–400 °C to avoid chipping.
Can Pure W be welded?
Essentially unweldable by arc processes — electron-beam or laser welding in high vacuum with preheat is possible but the weld recrystallizes and becomes brittle; joining is normally by brazing (Ni-, Cu-, Ag-Cu-Ti fillers) or mechanical/diffusion bonding.
Can Pure W be formed, bent or molded?
No practical cold forming; roll, swage, forge or bend hot (typically 1000–1500 °C, above the DBTT) with intermediate stress-relief anneals; complex shapes come from powder pressing, CIP+sinter+HIP or LPBF.
Pure W 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 |
|---|---|---|
| Mo | ≤ 0.01 | 0 |
| Fe | ≤ 0.01 | 0 |
| Ni | ≤ 0.01 | 0 |
| C | ≤ 0 | 0 |
| Ohigher in as-sintered and printed material | ≤ 0.01 | 0 |
| Si | ≤ 0 | 0 |
| Al | ≤ 0 | 0 |
| Ca | ≤ 0 | 0 |
| Cr | ≤ 0 | 0 |
| Cu | ≤ 0 | 0 |
| Mg | ≤ 0 | 0 |
| Kdoped (AKS) wire grades intentionally higher | ≤ 0 | 5×10⁻⁴ |
| WPurity on a metallic basis, ASTM B760/GB/T 3875 class | ≥ 99.95 (balance) |
What surface finishes work on Pure W?
Not anodizable; grind and lap to a fine finish, then electropolish or acid-clean; for oxidation service above 500 °C apply Si/aluminide, CVD/PVD or Ni/Cr diffusion coatings, and use Ni or Au plating for solderability.
Equivalent designations
Standards and trade names that resolve to Tungsten Alloy Pure W in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Trade names
- CP Tungsten
How much does Pure W cost?
Pure W is a specialty-cost tungsten alloy ($$$$$), pricier than about 99% 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.
Pure W — frequently asked
What is Pure W used for?
Pure W is typically used for X-ray tube anodes, radiation shielding blocks and collimators, GTAW welding electrodes, furnace hot-zone elements and shields, ion- and plasma-facing components and EDM electrodes. In short: high-density tungsten rod.
What is the yield strength of Pure W?
Pure W has a typical yield strength of 700 MPa (102 ksi) and a tensile strength of 800 MPa (116 ksi) — weaker than 61% of tungsten alloy grades. Strength varies by condition: see the 7 listed tempers.
Is Pure W easy to machine?
Not especially — machinability is rated not recommended (8/100, worse than 71% of tungsten alloy grades). Treat as a brittle hard metal: grinding, EDM/wire-EDM and laser cutting are preferred; if turning/milling, use rigid setups, negative-rake carbide or CBN, low speed, heavy flood coolant and preheat 200–400 °C to avoid chipping.
Can Pure W be welded?
Not readily — weldability is rated not recommended (10/100). Essentially unweldable by arc processes — electron-beam or laser welding in high vacuum with preheat is possible but the weld recrystallizes and becomes brittle; joining is normally by brazing (Ni-, Cu-, Ag-Cu-Ti fillers) or mechanical/diffusion bonding.
What surface finishes work on Pure W?
Not anodizable; grind and lap to a fine finish, then electropolish or acid-clean; for oxidation service above 500 °C apply Si/aluminide, CVD/PVD or Ni/Cr diffusion coatings, and use Ni or Au plating for solderability.
Can Pure W be formed, bent or molded?
No practical cold forming; roll, swage, forge or bend hot (typically 1000–1500 °C, above the DBTT) with intermediate stress-relief anneals; complex shapes come from powder pressing, CIP+sinter+HIP or LPBF.
What is the maximum service temperature of Pure W?
Pure W is rated for continuous use to about 500°C (932 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Pure W As Rolled and Pure W-HIP?
As Rolled is the default condition — default stocked wrought condition for plate, sheet and foil: highest strength and hardness, fibrous texture, minimum room-temperature ductility still usable for flat parts and shielding. HIP: pick for large, complex or additively made W parts needing pore-free, leak-tight, isotropic material without a wrought texture. Yield strength is 700 MPa in As Rolled versus 380 MPa in HIP.
How much does Pure W cost?
Pure W is a specialty-cost tungsten alloy ($$$$$), pricier than about 99% 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 B760 – Tungsten Plate, Sheet and Foil — ASTM (2022)
- ASTM B777 / ASTM B459 tungsten product specifications — ASTM (2020)
- GB/T 3875 / GB/T 4181 — SAC (2017)
- ASM Handbook Vol.2 — Properties of Refractory Metals — ASM International (1990)
- Tungsten material properties (sintered, rolled, forged, wire) — Plansee SE (2023)
- Pure tungsten product data — Midwest Tungsten Service (2023)
- CRC Handbook of Chemistry and Physics — physical constants of W — CRC Press (2020)
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.