ASTM B392 Niobium and Niobium Alloy Bar, Rod, and Wire
- Type: Bar, Rod, Wire
- R04200 Type 1—Reactor grade unalloyed Niobium.
- R04210 Type 2—Commercial grade unalloyed Niobium.
- R04251 (NbZr1) Type 3—Reactor grade Niobium alloy containing 1 % Zirconium.
- R04261 (NbZr1) Type 4—Commercial grade Niobium alloy containing 1 % Zirconium.
ASTM B392 Niobium and Niobium Alloy Bar, Rod, and Wire
ASTM B392 covers high-purity niobium and niobium alloy bar, rod, and wire products, including commonly used grades such as Nb1, Nb2, NbZr1, and other niobium-based alloys for demanding industrial applications. These materials offer excellent corrosion resistance, high melting point performance, good formability, and reliable strength in elevated-temperature and vacuum environments, making them well suited for aerospace, chemical processing, electronics, superconducting systems, medical devices, and advanced industrial equipment. Manufactured strictly to ASTM B392 standards and available in a variety of sizes, conditions, and surface finishes, Golden Sunbird Metals’ niobium bar, rod, and wire products deliver dependable quality, full traceability, and precise performance for critical engineering requirements.
R04200-Type 1—Reactor grade unalloyed niobium
R04210-Type 2—Commercial grade unalloyed niobium
R04251 (NbZr1)-Type 3—Reactor grade Niobium alloy containing 1 % Zirconium.
R04261 (NbZr1)-Type 4—Commercial grade Niobium alloy containing 1 % Zirconium.
ASTM B392 Niobium and Niobium Alloy Bar, Rod, and Wire Chemical Composition (wt.%)
| Elements | R04200-Type 1 | R04210-Type 2 | R04251 (NbZr1)-Type 3 | R04261 (NbZr1)-Type 4 |
| C | 0.01 | 0.01 | 0.01 | 0.01 |
| N | 0.01 | 0.01 | 0.01 | 0.01 |
| O | 0.015 | 0.015 | 0.015 | 0.015 |
| H | 0.0015 | 0.0015 | 0.0015 | 0.0015 |
| Zr | 0.02 | 0.02 | 0.8-1.2 | 0.8-1.2 |
| Ta | 0.1 | 0.3 | 0.1 | 0.5 |
| Fe | 0.005 | 0.01 | 0.005 | 0.01 |
| Si | 0.005 | 0.005 | 0.005 | 0.005 |
| W | 0.03 | 0.05 | 0.03 | 0.05 |
| Ni | 0.005 | 0.005 | 0.005 | 0.005 |
| Mo | 0.01 | 0.02 | 0.01 | 0.05 |
| Hf | 0.02 | 0.03 | 0.02 | 0.03 |
| Ti | 0.02 | 0.03 | 0.02 | 0.03 |
| B | 2ppm | – | 2ppm | – |
| Al | 0.002 | 0.005 | 0.002 | 0.005 |
| Be | 0.005 | – | 0.005 | – |
| Cr | 0.002 | – | 0.002 | – |
| Co | 0.002 | – | 0.002 | – |
| Nb | remainder | remainder | remainder | remainder |
Additional Chemical Requirements for Finished Product (When Specified by the Purchaser)
| Elements | R04200-Type 1 | R04210-Type 2 | R04251 (NbZr1)-Type 3 | R04261 (NbZr1)-Type 4 |
| O | 0.025 | 0.04 | 0.025 | 0.04 |
| C | 0.01 | 0.015 | 0.01 | 0.015 |
| N | 0.01 | 0.01 | 0.01 | 0.01 |
| H | 0.0015 | 0.0015 | 0.0015 | 0.0015 |
ASTM B392 Niobium and Niobium Alloy Bar, Rod, and Wire Brinell Hardness
| Elements | R04200-Type 1 | R04210-Type 2 | R04251 (NbZr1)-Type 3 | R04261 (NbZr1)-Type 4 |
| Maximum average | 90 | 125 | 125 | 135 |
| Maximum per individual impression | 105 | 150 | 140 | 150 |
ASTM B392 Niobium and Niobium Alloy Bar, Rod, and Wire Annealed Condition (90 % Minimum Recrystallized) Mechanical Properties
| Grade | Ultimate tensile strength, min., psi (MPa) | Yield strength, min., psi (MPa) | Elongation, min., % 1 Inch (25.4mm) gauge |
| Rod, 0.125 in. (3.18 mm) to 2.5 in. (63.5 mm) diameter | |||
| R04200-1/R04210-2 | 18000 (125) | 10500 (73) | 25 |
| R04251-3/R04261-4 (NbZr1) | 28000 (195) | 18000 (125) | 20 |
| Wire, 0.020 in. (0.51 mm) to 0.124 in. (3.145 mm) | |||
| R04200-1/R04210-2 | 18000 (125) | …….. | 20 |
| R04251-3/R04261-4 (NbZr1) | 28000 (195) | …….. | 15 |
Features
- ASTM B392 wrought niobium and niobium alloy bar, rod, and wire in reactor grade and commercial grade options.
- Available grades include R04200, R04210, R04251, and R04261.
- R04251-Type 3 and R04261-Type 4 are niobium-zirconium alloys containing approximately 1% zirconium.
- Nb-1Zr offers improved creep strength and better elevated-temperature performance compared with commercially pure niobium.
- Niobium and Nb-1Zr retain good chemical resistance, high melting temperature, and low thermal neutron capture cross-section.
- Suitable for precision processing into straight lengths, coils, spools, or reels depending on product form.
Technical Specifications
| Specification | Value |
| Standard | ASTM B392 Niobium and Niobium Alloy Bar, Rod and Wire |
| Grade | R04200-Type 1, R04210-Type 2, R04251 (NbZr1)-Type 3, R04261 (NbZr1)-Type 4 |
| Finish | Clean, bright finish, free of defects and surface imperfections. |
| Type | Bar, Rod, Wire |
| Bar | Material less than 6 in. (152.4 mm) in width and 0.187 in. (4.75 mm) or greater in thickness, with a rectangular cross-section supplied in straight lengths. |
| Rod | Material 0.125 to 2.50 in. (3.18 to 63.50 mm) in diameter, in round, hexagonal, or octagonal cross sections supplied in straight lengths. |
| Wire | Material 0.020 to 0.124 in. (0.51 to 3.15 mm) in diameter, furnished in coils or on spools or reels. Material less than 0.020 in. (0.51 mm) in diameter is not covered by this specification. |
| Inspection Certificate | EN 10204 Type 3.1 (Mill Test Certificate), EN 10204 Type 3.2 (Witness Testing or 3rd Party Inspection) |
| Tests | Chemical analysis, Tensile test, Hardness test, and Microstructural examination |
Packing & Shipment
To ensure product safety during storage, handling, and international transportation, niobium and niobium alloy (ASTM B392) bars, rods, and wires (including R04200, R04210, R04251, and R04261 grades) are packed with corrosion protection and impact protection measures according to product size, quantity, and shipping mode.
| Item | Packing / Shipment Method |
| Internal Protection | Bars, rods, and wires are thoroughly cleaned, dried, and free of all contaminants before packing; all surfaces receive a temporary protective film or oil-free coating suitable for refractory metals. |
| Sealing Protection | Each bundle, coil, or individual piece is placed in sealed PE bags or vacuum-sealed packaging to prevent dust, moisture, and oxidation. |
| Surface Protection | Critical bright-finish surfaces are covered with soft non-woven fabric, EPE foam liners, or acid-free protective paper to prevent scratches and maintain surface condition. |
| Individual Packing | Smaller diameter rods, bars, and wire spools/coils are individually wrapped with PE film and packed in sturdy plywood boxes or export-grade wooden crates with sufficient cushioning materials. |
| Large / Long Bar & Rod Packing | Longer bars or heavy rods are bundled, clearly labeled, and secured on wooden pallets or reinforced export crates; each bundle includes handling instructions where applicable. |
| Wire Coil / Spool Packing | Wires are wound onto sturdy wooden, plastic, or metal spools/coils, wrapped with protective film, and placed in individual crates or pallets to prevent unwinding or deformation. |
| Shock Protection | High-density foam padding, internal bracing, wooden blocking, and heavy-duty strapping are used to prevent movement and impact during transit. |
| Moisture Control | Desiccant bags and humidity indicator cards are placed inside the sealed package to control moisture and prevent oxidation. |
| Marking | Package labels include product name, grade (R04200 / R04210 / R04251 / R04261), dimensions, condition (annealed / cold worked / stress-relieved), quantity, net/gross weight, heat number, and shipping marks. |
| Shipping Mode | By sea (FCL / LCL), air freight, or multimodal transport depending on order quantity and delivery requirements. |
| Documents | Packing list, commercial invoice, certificate of origin, material test certificates (EN 10204 3.1 / 3.2), chemical analysis reports, and inspection documents provided. |
Applications
R04200 (Commercially Pure Niobium, Reactor Grade)
- Nuclear industry components requiring low thermal neutron capture cross-section and high purity.
- Chemical processing equipment exposed to aggressive acids and corrosive media.
- High-temperature furnace components and vacuum systems where ductility and formability are critical.
- Research and laboratory applications requiring high-purity niobium material.
R04210 (Commercially Pure Niobium, Commercial Grade)
- General industrial applications where good corrosion resistance and workability are required.
- Fabrication into custom components, fasteners, and formed parts.
- Chemical equipment operating under moderate temperature and corrosion conditions.
- Cost-sensitive applications where reactor-grade purity is not required.
R04251 (Type 3 – NbZr1 Alloy)
- Nuclear industry components requiring improved creep strength and low neutron absorption.
- High-pressure sodium (HPS) lamp components, especially wire and rod elements.
- High-temperature service parts such as load-free thermal shields and furnace internals.
- Structural components in elevated-temperature environments where better mechanical stability than pure niobium is required.
R04261 (Type 4 – NbZr1 Alloy, Higher Strength Variant)
- Advanced nuclear and energy systems requiring enhanced high-temperature mechanical performance.
- Components operating under long-term thermal exposure with creep resistance requirements.
- Precision high-temperature assemblies where dimensional stability is critical.
- Specialized industrial and research applications needing a balance of strength, corrosion resistance, and fabricability.
