ASTM B394 Niobium and Niobium Alloy Tube
- Type: Seamless and Welded Tube
- 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 B394 Seamless and Welded Niobium and Niobium Alloy Tube
ASTM B394 niobium and niobium alloy tube are engineered for applications that demand excellent corrosion resistance, high-temperature stability, and dependable performance in aggressive service environments. Available in commonly used grades such as Nb1, Nb2, NbZr1, and other niobium-based alloys, these tubes are well suited for chemical processing, aerospace, vacuum systems, superconducting equipment, and advanced industrial applications. With good formability, reliable weldability, and stable mechanical properties, ASTM B394 tubes provide a practical solution for critical systems where purity, strength, and durability are essential.
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 B394 Seamless and Welded Niobium and Niobium Alloy Tube Chemical Composition (wt.%)
| Element/Property | Type 1 (R04200) | Type 2 (R04210) | Type 3 (R04251 / NbZr1) | Type 4 (R04261 / NbZr1) |
| Carbon (C) | Max 0.01% | Max 0.01% | Max 0.01% | Max 0.01% |
| Nitrogen (N) | Max 0.01% | Max 0.01% | Max 0.01% | Max 0.01% |
| Oxygen (O) | Max 0.015% | Max 0.025% | Max 0.015% | Max 0.025% |
| Hydrogen (H) | Max 0.0015% | Max 0.0015% | Max 0.0015% | Max 0.0015% |
| Zirconium (Zr) | – | – | 0.8 to 1.2% (Range) | 0.8 to 1.2% (Range) |
| Tantalum (Ta) | Max 0.1% | Max 0.3% | Max 0.1% | Max 0.5% |
| Iron (Fe) | Max 0.005% | Max 0.01% | Max 0.005% | Max 0.01% |
| Silicon (Si) | Max 0.005% | Max 0.005% | Max 0.005% | Max 0.005% |
| Tungsten (W) | Max 0.03% | Max 0.05% | Max 0.03% | Max 0.05% |
| Nickel (Ni) | Max 0.005% | Max 0.005% | Max 0.005% | Max 0.005% |
| Molybdenum (Mo) | Max 0.010% | Max 0.020% | Max 0.010% | Max 0.050% |
| Hafnium (Hf) | Max 0.02% | Max 0.02% | Max 0.02% | Max 0.02% |
| Titanium (Ti) | Max 0.02% | Max 0.03% | Max 0.02% | Max 0.03% |
| Brinell Hardness | 90 (Avg), 105 (Max) | 125 (Avg), 150 (Max) | 125 (Avg), 140 (Max) | 135 (Avg), 150 (Max) |
ASTM B394 Seamless and Welded Niobium and Niobium Alloy Tube Mechanical Properties
| Grade | Ultimate Tensile Strength (min) | Yield Strength (0.2% offset, min) | Elongation in 1-inch (25-mm) Gage Length (min) |
| Type 1 | 18,000 psi (125 MPa) | 10,500 psi (73 MPa) | 25% |
| Type 2 | 18,000 psi (125 MPa) | 10,500 psi (73 MPa) | 25% |
| NbZr1 Type 3 | 28,000 psi (195 MPa) | 18,000 psi (125 MPa) | 20% |
| NbZr1 Type 4 | 28,000 psi (195 MPa) | 18,000 psi (125 MPa) | 20% |
Features
- Manufactured to ASTM B394/B394M for seamless and welded niobium and niobium alloy tubes.
- Available in R04200-Type 1, R04210-Type 2, R04251-Type 3, and R04261-Type 4.
- R04251-Type 3 and R04261-Type 4 are niobium-zirconium alloys containing approximately 1% zirconium.
- Nb-1Zr improves creep strength and elevated-temperature performance compared with commercially pure niobium, while retaining niobium’s chemical resistance and low thermal neutron capture cross-section.
- Good fabricability and ductility make these tubes suitable for demanding fabrication and forming operations.
- Supplied in a clean, bright finish with options for seamless and welded construction.
Packing & Shipment
To ensure product safety during storage, handling, and international transportation, ASTM B393 niobium sheet, plate, and strip are packed with surface protection and moisture-control measures according to product size, quantity, and shipping mode.
| Item | Packing / Shipment Method |
| Internal Protection | Sheets, plates, and strips are cleaned and dried before packing, and all surfaces are kept free from dust, oil, and other contaminants. |
| Sealing Protection | Each piece is separated and sealed in PE bags or wrapped with protective film to reduce moisture and oxidation risk. |
| Surface Protection | Bright or finished surfaces are covered with soft non-woven fabric, acid-free paper, or EPE foam to prevent scratches and edge damage. |
| Individual Packing | Smaller sheets and strips are individually wrapped and packed in plywood boxes or export-grade wooden crates with cushioning materials. |
| Large Sheet / Plate Packing | Larger sheets and plates are placed on pallets or in reinforced wooden crates, with corner protection and secure strapping to avoid bending or impact. |
| Strip Packing | Strips are coiled or laid flat according to size, then wrapped and fixed in strong cartons, crates, or pallets to maintain shape and surface condition. |
| Shock Protection | Foam padding, internal bracing, and heavy-duty strapping are used to prevent movement during transit. |
| Moisture Control | Desiccant bags and humidity protection materials are added inside the package when required. |
| Marking | Package labels include product name, grade, dimensions, condition, quantity, net/gross weight, heat number, and shipping marks. |
| Shipping Mode | By sea, air freight, or multimodal transport depending on order quantity and delivery requirements. |
| Documents | Packing list, commercial invoice, certificate of origin, material test certificates, and inspection documents can be provided. |
Technical Specifications
| Specification | Value |
| Standard | ASTM B394 Niobium and Niobium Alloy Tube |
| 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 |
| Seam Type | Seamless and Welded |
| OD | 4.7-101.6mm |
| WT | 0.5-20mm |
| Length | 100-6000mm |
| 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 |
Applications
R04200 (Type 1 – Reactor Grade Unalloyed Niobium)
- Chemical processing equipment, including heat exchangers and condensers operating in corrosive media.
- Nuclear-related components where low neutron absorption and high purity are required.
- Vacuum systems and high-temperature furnace components that require excellent corrosion resistance and formability.
R04210 (Type 2 – Commercial Grade Unalloyed Niobium)
- General industrial chemical equipment where corrosion resistance and workability are important.
- Fabricated parts for moderate-temperature service in chemical or high-purity process environments.
- Cost-sensitive applications that do not require reactor-grade purity.
R04251 (Type 3 – Reactor Grade Nb-1Zr)
- Nuclear industry components requiring improved high-temperature strength and low neutron capture.
- High-temperature structural or support parts where creep resistance matters.
- Load-free thermal shields and other elevated-temperature vacuum-system parts.
R04261 (Type 4 – Commercial Grade Nb-1Zr)
- Commercial high-temperature components where better strength is needed than pure niobium can provide.
- Furnace hardware, thermal shields, and other hot-zone assemblies.
- Corrosion-resistant tubes for advanced industrial and research equipment.
