Alloy 903,Incoloy 903 Bar(Round bar, Flat bar),,E FORU

British Specs:，American Specs:，German Specs:

**Product Introduction: Alloy 903 / Incoloy 903 Bar (Round Bar & Flat Bar) UNS N19903** **Overview** Incoloy 903 bars represent the wrought bar product form of this nickel-iron-cobalt low thermal expansion superalloy. Available as round bars and flat bars, this age-hardenable material is specifically engineered to maintain exceptional dimensional stability under thermal cycling conditions while delivering high strength from cryogenic temperatures up to 500°C (930°F). The bar form is particularly suited for machining precision components that require tight tolerances and stable mechanical properties in demanding thermal environments. **Key Characteristics** * **Controlled Low Thermal Expansion:** Maintains consistent dimensions during temperature fluctuations * **High Strength-to-Weight Ratio:** Excellent mechanical properties achieved through age-hardening * **Superior Machinability:** Good machinability in solution-annealed condition * **Age-Hardenable:** Develops high strength through precipitation hardening treatment * **Thermal Stability:** Maintains properties across wide temperature range (-250°C to +500°C) * **Good Fatigue Resistance:** Withstands cyclic loading conditions --- **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% | | Reduction of Area | 18-28% | | Hardness | 36-42 HRC | --- **Product Applications** * **Aerospace Components:** Gas turbine engine rings, seals, shafts, and structural members * **Precision Instruments:** Dimensionally stable frames, supports, and optical mounts * **Automotive Turbochargers:** High-temperature components requiring thermal stability * **Nuclear Applications:** Control rod mechanisms and reactor structural components * **Optical Systems:** Mounting hardware, mirror mounts, and structural elements * **Specialized Fasteners:** High-strength bolts, studs, and custom fasteners * **Machine Components:** Jigs, fixtures, and tooling for high-temperature applications --- **International Standards & Specifications** * **ASTM Standards:** - ASTM B637: Precipitation-Hardening Nickel Alloy Bars, Forgings, and Forging Stock for High-Temperature Service * **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 Bar Forms:** - **Round Bars:** 5mm to 300mm diameter - **Flat Bars:** 10mm to 200mm width, 3mm to 100mm thickness - **Surface Conditions:** Black, ground, polished, or turned - **Length:** Random mill lengths or cut-to-size * **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 bars are typically supplied in the solution-annealed condition for optimum machinability, with final age-hardening performed after machining to achieve full mechanical properties. Special care must be taken during heat treatment to avoid surface contamination. **Disclaimer:** The information provided is for reference purposes. Properties may vary based on manufacturing process, heat treatment, and bar size. For critical applications, always consult the manufacturer's technical data sheets and complete material certifications.

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 3017 gallon liquid totes Special package is available on request.