Vacuum Refractory · Niobium
Refractory Metal Pure Nb
Refractory Metal Pure Nb is a vacuum refractory refractory metal — superconductor-grade niobium. Typical values: 195 MPa yield, 8.57 g/cm³, rated to 2,000 °C. Available for CNC machining, Sheet metal at FabDigit.
Properties
Typical room-temperature values in the Vacuum Annealed condition. Metric first, imperial in gray. The bars show where Pure Nb sits against the other 8 refractory metal grades in the catalog.
Datasheet
| Yield strength | 195 MPa28 ksi |
|---|---|
| Tensile strength | 275 MPa40 ksi |
| Hardness | 85 HV≈ 81 HB |
| Density | 8.57 g/cm³0.31 lb/in³ |
| Specific strength (yield ÷ density) | 23 |
| Min service temp | -200 °C-328 °F |
| Max service temp | 2,000 °C3,632 °F |
| Electrical conductivity | 11 % IACS6.4 MS/m |
| Machinability | Fair40 / 100 |
| Weldability | Good60 / 100 |
| Formability | Very good75 / 100 |
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Against other refractory metal grades
Strength versus weight in the refractory metal family
Yield strength against density for every refractory metal grade FabDigit runs. Pure Nb is highlighted; hover a dot for its name, or open the interactive family chart.
Manufacturability
The process limits FabDigit's quote engine applies to Pure Nb. Design inside these and the part quotes instantly; outside them it routes to an engineer.
CNC machining
| Machinability | Fair40 / 100 |
|---|---|
| Cutting speed (rough / finish) | — / — |
| Minimum wall | — |
| Minimum internal radius | — |
| Drill depth limit | — |
| Best surface (machined / polished) | Ra — / — |
| Hardenable after machining | — |
Sheet metal
| Formability | Better75 / 100 |
|---|---|
| Weldability | Good60 / 100 |
| Bendable | Yes |
Conditions and tempers
How Pure Nb is supplied and what each state is for. The default is what FabDigit quotes unless your drawing says otherwise.
| Condition | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Vacuum AnnealedDefault Heat Treat State | Contamination-free Ti/Zr — implants, aerospace hardware | — | — | — | — |
As Rolled Cold Work | Mill state, no property guarantee — non-structural use | — | — | — | — |
Heat treatment and post-processing
Operations FabDigit's suppliers routinely run on Pure Nb, ranked by how often they make sense for this grade.
Post-processing
| Manual Deburr | Deburrstandard |
|---|---|
| Edge Break (0.5mm) | Deburr |
| CMM Inspection | Inspection |
| FAI Report | Inspection |
| Individual Bag | Packaging |
Surface finishes for Pure Nb
Coatings and treatments compatible with refractory metal on the processes Pure Nb runs on. Pick them in the quote configurator or call them out on the drawing.
Marking / Decoration
- Chemical Etching
- Dot Peen Marking
- Electro-chemical Etching
- Embossing / Debossing
- Ink Stamping
- Laser Marking
- Mechanical Engraving
- Steel Stamping
- Vibro Engraving / Scribing
Equivalent designations
Standards and trade names that resolve to Refractory Metal Pure Nb in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- R04200
- Trade names
- Columbium
- Other
- Niobium 99.9
Stock forms
Raw-material forms FabDigit sources Pure Nb in.
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.