IN 909 Centri-Vac Nickel Cobalt Based Alloy,，1

### **Product Introduction: INCONEL® Alloy 909 (IN 909) Centri-Vac™ Nickel-Cobalt Based Alloy** **Overview** INCONEL® Alloy 909 is a low-thermal-expansion, precipitation-hardenable nickel-cobalt-iron superalloy. The "Centri-Vac" designation indicates components produced via specialized centrifugal casting and vacuum melting processes, ensuring exceptional metallurgical purity, homogeneity, and performance. This alloy is specifically engineered for applications requiring controlled thermal expansion, high strength, and excellent fatigue resistance over a wide temperature range, from cryogenic conditions up to 650°C (1200°F). Its unique combination of properties makes it indispensable for tight-clearance, high-speed rotating equipment in aerospace and power generation. --- #### **Chemical Composition (Typical % by Weight)** The composition of Alloy 909 is meticulously balanced to achieve its low thermal expansion characteristics and high strength. | Element | Content (%) | Role & Benefit | | :--- | :--- | :--- | | **Nickel (Ni)** | 35.0 - 40.0 | Forms the primary matrix and is critical for achieving a low coefficient of thermal expansion. | | **Cobalt (Co)** | 12.0 - 16.0 | Enhances strength and stability at high temperatures and contributes to the low expansion behavior. | | **Iron (Fe)** | Balance | Complements the nickel-cobalt matrix. | | **Niobium (Nb)** | 4.3 - 5.2 | The primary precipitation hardening element, forming the gamma double prime (γ") phase, Ni₃Nb, for high strength. | | **Titanium (Ti)** | 1.3 - 1.8 | Works synergistically with niobium in the precipitation hardening process and helps control thermal expansion. | | **Silicon (Si)** | 0.25 - 0.50 | Aids in castability and contributes to strength. | | **Aluminum (Al)** | 0.15 max | A residual element. | | **Carbon (C)** | 0.06 max | A residual element. | | **Boron (B)** | 0.012 max | Enhances creep strength and ductility. | *Note: "INCONEL" is a registered trademark of Special Metals Corporation. "Centri-Vac" refers to a proprietary centrifugal casting and vacuum melting process.* --- #### **Physical & Mechanical Properties (Typical - Aged Condition)** | Property | Value / Condition | | :--- | :--- | | **Density** | 8.25 g/cm³ (0.298 lb/in³) | | **Melting Range** | 1365 - 1425 °C (2490 - 2600 °F) | | **Coefficient of Thermal Expansion** | 9.5 μm/m·°C (5.3 μin/in·°F) @ 20-400°C | | **Thermal Conductivity**| 14.0 W/m·K (97 BTU·in/hr·ft²·°F) @ 100°C | | **Tensile Strength** | 1100 MPa (160 ksi) min | | **Yield Strength (0.2% Offset)** | 860 MPa (125 ksi) min | | **Elongation** | 10% min | --- #### **International Standards and Specifications** While specific "Centri-Vac" castings are often proprietary, the alloy itself is governed by strict standards. * **AMS 5713:** This is the primary Aerospace Material Specification for the wrought form of Nickel-Iron-Cobalt Alloy (UNS N09909) bar, forgings, and rings, defining the required chemistry and properties. * **Proprietary Casting Specifications:** Centri-Vac cast components of IN 909 are typically produced to proprietary internal specifications derived from AMS standards, ensuring the highest quality for investment or centrifugal castings. --- #### **Product Applications** IN 909 Centri-Vac components are critical in applications where dimensional stability under thermal cycling is paramount. 1. **Aerospace & Gas Turbines:** * **Turbine Seals and Shrouds:** Where maintenance of tight clearances at high operating temperatures is crucial for engine efficiency. * **Casings and Support Structures:** Components that must resist thermal growth to maintain alignment with rotating parts. * **Afterburner Components.** 2. **Power Generation:** * **Gas Turbine Seals and Rings** in industrial and utility turbines. * **Components in Steam Turbines** where thermal stability is required. #### **Key Advantages** * **Controlled Low Thermal Expansion:** Its most defining feature, providing exceptional dimensional stability over a wide temperature range, which is critical for maintaining tight clearances. * **High Strength:** Achieves high tensile and yield strength through precipitation hardening, allowing it to withstand significant mechanical loads. * **Good Fatigue Resistance:** Excellent resistance to thermal and mechanical fatigue, essential for components undergoing repeated thermal cycles. * **Excellent Fabricability:** The Centri-Vac process allows for the creation of complex, near-net-shape components with superior metallurgical integrity. **Conclusion** INCONEL® Alloy 909 Centri-Vac represents a specialized class of high-performance superalloys designed for extreme thermal management challenges. Its unique low thermal expansion coefficient, combined with high strength and excellent fatigue life, makes it the material of choice for critical sealing and structural components in advanced aerospace engines and power generation turbines. For engineers designing systems where thermal growth must be minimized to ensure efficiency, performance, and reliability, IN 909 Centri-Vac castings offer a proven, high-integrity solution.

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 3410 gallon liquid totes Special package is available on request.