Alloy 903,Incoloy 903 Tube,,E FORU

British Specs:，American Specs:，German Specs:

**Product Introduction: Alloy 903 / Incoloy 903 Tube (UNS N19903)** **Overview** Incoloy 903 tube is a low thermal expansion superalloy product form specifically engineered for applications requiring exceptional dimensional stability under thermal cycling conditions. This nickel-iron-cobalt alloy maintains consistent dimensions across a wide temperature range while providing high strength and excellent fatigue resistance. The tube form is particularly suitable for high-precision instrumentation, hydraulic systems, and heat exchanger applications where controlled thermal expansion is critical for system performance and reliability. **Key Characteristics** * **Controlled Low Thermal Expansion Coefficient (CTE)** * **High Strength at Elevated Temperatures** * **Excellent Fatigue and Creep Resistance** * **Good Fabricability and Weldability** * **Age-Hardenable for Enhanced Mechanical Properties** * **Maintains Mechanical Properties from Cryogenic to 500°C** --- **Chemical Composition (Weight %)** | Element | Content (%) | |---------|-------------| | Nickel (Ni) | 36.0 - 39.0 | | Iron (Fe) | Balance | | Cobalt (Co) | 14.0 - 17.0 | | Niobium (Nb) + Tantalum (Ta) | 2.90 - 3.50 | | Titanium (Ti) | 1.35 - 1.75 | | Aluminum (Al) | 0.70 - 1.15 | | Silicon (Si) | ≤ 0.30 | | Manganese (Mn) | ≤ 0.20 | | Carbon (C) | ≤ 0.05 | | Sulfur (S) | ≤ 0.015 | | Boron (B) | ≤ 0.012 | --- **Physical Properties** | Property | Value | |----------|-------| | Density | 8.25 g/cm³ (0.298 lb/in³) | | Melting Range | 1370-1425°C (2500-2600°F) | | Mean Coefficient of Thermal Expansion | 8.5 × 10⁻⁶/°C (20-400°C) | | Thermal Conductivity | 11.5 W/m·K (at 100°C) | | Specific Heat | 440 J/kg·K (at 20°C) | | Electrical Resistivity | 1.05 μΩ·m | | Modulus of Elasticity | 148 GPa (21.5 × 10⁶ psi) | --- **Mechanical Properties (Age-Hardened Condition)** | Property | Value | |----------|-------------| | Tensile Strength | 1240-1380 MPa (180-200 ksi) | | Yield Strength (0.2% Offset) | 1030-1170 MPa (150-170 ksi) | | Elongation | 12-18% | | Hardness | 36-42 HRC | --- **Product Applications** * **Aerospace Systems:** Hydraulic lines, fuel injection tubes, instrument capillaries * **Power Generation:** Heat exchanger tubes, boiler instrumentation lines * **Chemical Processing:** Precision instrument tubing, sensor housings * **Nuclear Industry:** Reactor instrumentation tubes, control system components * **Advanced Engines:** Exhaust gas temperature sensing tubes * **Research Facilities:** Cryogenic transfer lines, vacuum chamber components * **Optical Industry:** Thermal management tubes for laser systems --- **International Standards & Specifications** * **ASTM Standards:** - ASTM B829: Standard Specification for Seamless Nickel and Nickel Alloy Condenser and Heat-Exchanger Tubes - ASTM B751: Standard Specification for General Requirements for Nickel and Nickel Alloy Seamless and Welded Tube * **Aerospace Materials Specifications:** - AMS 5916: Ring, Sealing, Low Thermal Expansion, Vacuum Melted, Solution and Precipitation Heat Treated * **International Designations:** - UNS N19903 - W. Nr. 2.4717 * **Available Tube Specifications:** - **Types:** Seamless and welded - **Outside Diameter:** 3mm to 100mm - **Wall Thickness:** 0.5mm to 10mm - **Tolerances:** To ASTM or customer specifications - **Surface Finish:** Pickled, polished, or bright annealed * **Heat Treatment:** - Solution Annealing: 980°C ±15°C, rapid cool - Aging Treatment: 720°C for 8 hours, furnace cool to 620°C for 8 hours, air cool --- **Note:** Incoloy 903 tubes are typically supplied in the solution-annealed condition for optimum fabricability. Final age-hardening is performed after all fabrication and machining operations. Special consideration should be given to welding procedures and subsequent heat treatment to maintain optimal properties. The material's low thermal expansion characteristic makes it particularly suitable for applications where thermal cycling could cause dimensional changes in conventional materials. **Disclaimer:** The information provided is for reference purposes. Properties may vary based on manufacturing process, heat treatment, and tube dimensions. For critical applications, always consult the manufacturer's technical data sheets and complete material certifications. Proper material selection should be verified through appropriate engineering analysis.

Packing of Standard Packing: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 3019 gallon liquid totes Special package is available on request.