Alloy 46,Glass sealing 46 Alloy Pipe,UNS K94600,E FORU

British Specs:，American Specs: ASTM F30，German Specs:

### **Alloy 46 (Glass Sealing 46) - Pipe Product Overview** **Alloy 46** is a low-expansion iron-nickel alloy specifically formulated for creating hermetic matched seals with soft glass. Its coefficient of thermal expansion (CTE) is engineered to closely match that of specific soda-lime and lead-alkali silicate glasses, preventing destructive stress during and after the sealing process. The **Pipe** form of this alloy is used for specialized applications where a sealed tubular conductor or a structural glass-metal interface is required. * **UNS Designation:** **K94600** * **Common Product Forms:** Pipe, Tube, Bar, Wire, Strip. --- #### **1. Chemical Composition** The chemical composition is precisely controlled to ensure consistent thermal and physical properties critical for reliable sealing. | Element | Percentage (%) | Role in the Alloy | | :--- | :--- | :--- | | **Nickel (Ni)** | 45.0 - 47.0 | Primary element defining the Curie point and thermal expansion characteristics. | | **Iron (Fe)** | Balance | Base element of the alloy. | | **Manganese (Mn)** | 0.10 - 0.30 | Aids in deoxidation during melting and improves hot workability. | | **Silicon (Si)** | 0.10 - 0.30 | Improves oxidation resistance and fluidity during the glass sealing process. | | **Carbon (C)** | 0.05 max | Kept low to prevent embrittlement and ensure good ductility. | | **Sulfur (S)** | 0.02 max | Impurity, kept low to prevent hot shortness. | | **Phosphorus (P)** | 0.02 max | Impurity, kept low to maintain ductility. | --- #### **2. Physical Properties** The physical properties are defined by its unique thermal expansion behavior, which is the cornerstone of its application. | Property | Value / Condition | Notes | | :--- | :--- | :--- | | **Density** | 8.18 g/cm³ (0.295 lb/in³) | | | **Melting Point** | ~1427 °C (2600 °F) | | | **Curie Temperature** | ~430 °C (805 °F) | The temperature at which the alloy loses its ferromagnetism. This is a critical point where the CTE curve changes. | | **Thermal Expansion Coefficient (CTE)** | 20 - 300°C: ~9.6 μm/m·°C (5.3 μin/in·°F)
20 - 450°C: ~10.6 μm/m·°C (5.9 μin/in·°F) | The CTE closely matches that of soft glasses (e.g., Corning 0080, 0120, 0010, 9010, 9040). | | **Thermal Conductivity** | 14.9 W/m·K (103 Btu·in/hr·ft²·°F) at 20°C | | | **Specific Heat** | 0.46 J/g·°C (0.11 Btu/lb·°F) at 20°C | | | **Electrical Resistivity** | 0.49 μΩ·m at 20°C | | | **Magnetic Properties** | Ferromagnetic at room temperature. Becomes paramagnetic above its Curie point. | | --- #### **3. Mechanical Properties (Typical - Annealed Condition)** Alloy 46 pipe is typically supplied in the annealed state to ensure maximum ductility for subsequent forming and sealing operations. * **Tensile Strength:** 517 - 586 MPa (75 - 85 ksi) * **Yield Strength (0.2% Offset):** 276 - 345 MPa (40 - 50 ksi) * **Elongation:** 30 - 40% * **Modulus of Elasticity:** 152 GPa (22 x 10⁶ psi) * **Hardness (Rockwell B):** 65 - 80 --- #### **4. Product Forms & Specific Applications** **Glass Sealing 46 Alloy Pipe** * **Description:** Alloy 46 Pipe is a tubular product used in applications requiring a hermetic glass-to-metal seal along its circumference. It can be supplied in various diameters and wall thicknesses. The surface is often clean and descaled, and may be copper-plated to prevent oxidation during storage and to promote excellent glass wetting during the sealing process. * **Primary Applications:** * **Terminal Housings & Envelope Seals:** Used as the primary metal component for the body of high-power vacuum tubes, microwave tubes, laser tubes, and X-ray tubes, where glass is sealed directly to the ends or sides of the pipe to create the vacuum envelope. * **Hermetic Feedthroughs:** Used as a sleeve or conduit for passing materials or signals through a wall while maintaining a vacuum or pressure seal. The glass is sealed into the annular space between the Alloy 46 pipe and an internal conductor. * **Viewports & Windows:** The pipe can be used as the flange to which a glass viewport is sealed, providing a visual window into a vacuum or pressure chamber. * **Specialized Sensor Housings:** Used in environments where the sensor element must be isolated within a hermetic, glass-sealed metal casing. --- #### **5. International Standards** While often custom-ordered, Alloy 46 Pipe generally conforms to the chemical and physical requirements of the following standards. | Standard Type | Standard Number | Title / Specification | | :--- | :--- | :--- | | **ASTM** | **ASTM F15** | *Standard Specification for Iron-Nickel Sealing Alloys* (This is the primary governing specification). | | **ASTM** | ASTM F30 | *Standard Specification for Iron-Nickel Sealing Alloys in the Preoxidized Condition* | | **IEC** | IEC 60404-8-6 | *Metallic magnetic materials - Part 8-6: Specifications for individual materials - Soft magnetic metallic materials* | | **UNS** | **K94600** | Unified Numbering System designation. | | **Common Trade Names** | Glass Sealing 46, 46 Ni-Fe Alloy, ASTM F15 Alloy 46 | | --- **Summary** **Alloy 46 (UNS K94600) Pipe** is a specialized functional material designed for critical tubular glass-to-metal sealing applications. Its value lies in its precise physical property—a thermal expansion curve that matches soft glass—enabling the creation of durable, hermetic, and stress-free seals in complex geometries. While less common than wire or rod, the pipe form is essential for constructing the main envelopes and housings in high-performance electronic, scientific, and industrial vacuum devices. Compliance with standards like **ASTM F15** ensures the material's consistency and reliability for these demanding applications.

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 2485 gallon liquid totes Special package is available on request.