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

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

### **Alloy 46 (Glass Sealing 46) - Tube Product Overview** **Alloy 46** is a controlled expansion iron-nickel alloy specifically engineered for creating reliable hermetic seals with soft glass. The alloy's thermal expansion characteristics are carefully matched to specific types of glass, particularly soda-lime and lead-alkali silicate glasses, ensuring minimal thermal stress during sealing and throughout service life. The **Tube** form enables specialized applications requiring cylindrical glass-to-metal seals in electronic and industrial components. * **UNS Designation:** **K94600** * **Common Product Forms:** Seamless Tube, Welded Tube, Pipe, Bar, Wire, Strip --- #### **1. Chemical Composition** The chemical composition is strictly controlled to maintain consistent thermal expansion properties and sealing performance. | Element | Percentage (%) | Role in the Alloy | |:---|:---|:---| | **Nickel (Ni)** | 45.0 - 47.0 | Primary element controlling thermal expansion characteristics and Curie point | | **Iron (Fe)** | Balance | Base element providing structural matrix | | **Manganese (Mn)** | 0.10 - 0.30 | Improves hot workability and acts as deoxidizer | | **Silicon (Si)** | 0.10 - 0.30 | Enhances glass wetting and oxidation resistance | | **Carbon (C)** | 0.05 max | Limited to prevent embrittlement | | **Sulfur (S)** | 0.02 max | Controlled impurity | | **Phosphorus (P)** | 0.02 max | Controlled impurity | --- #### **2. Physical Properties** The physical properties are characterized by predictable thermal expansion behavior matching soft glass. | 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) | Critical transition point affecting thermal expansion | | **Thermal Expansion Coefficient (CTE)** | 20-300°C: ~9.6 μm/m·°C
20-450°C: ~10.6 μm/m·°C | Matches soft glasses (Corning 0080, 0120, 0010 series) | | **Thermal Conductivity** | 14.9 W/m·K at 20°C | | | **Specific Heat** | 0.46 J/g·°C at 20°C | | | **Electrical Resistivity** | 0.49 μΩ·m at 20°C | | | **Magnetic Properties** | Ferromagnetic below Curie point | | --- #### **3. Mechanical Properties (Typical - Annealed Condition)** Tubes are typically supplied in annealed condition for optimal forming and sealing characteristics. * **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 × 10⁶ psi) * **Hardness (Rockwell B):** 65-80 * **Formability:** Excellent in annealed condition --- #### **4. Product Forms & Specific Applications** **Glass Sealing 46 Alloy Tube** * **Description:** Alloy 46 tubes are produced as seamless or welded tubular products with precise dimensional tolerances. They are supplied with clean, oxide-free surfaces, often with copper plating to prevent oxidation and enhance glass wetting during the sealing process. Available in various diameters and wall thicknesses to meet specific design requirements. * **Primary Applications:** * **Hermetic Envelope Seals:** Used as the main structural component in vacuum tubes, electron tube envelopes, and high-power switching devices where glass is sealed to the tube ends. * **Lead-Through Assemblies:** Serves as the outer conductor in coaxial feedthroughs, providing the glass seal interface while maintaining electrical isolation. * **Sensor Housings:** Provides protective hermetic encapsulation for temperature, pressure, and chemical sensors in harsh environments. * **Optical Component Housings:** Used in laser tubes, optical display components, and specialized lighting where glass must be sealed to tubular metal sections. * **Laboratory Apparatus:** Employed in specialized laboratory equipment requiring reliable glass-to-metal seals in tubular configurations. --- #### **5. International Standards** Alloy 46 Tube conforms to established international standards for sealing alloys. | Standard Type | Standard Number | Title / Specification | |:---|:---|:---| | **ASTM** | **ASTM F15** | Standard Specification for Iron-Nickel Sealing Alloys | | **ASTM** | ASTM F30 | Specification for Iron-Nickel Alloys in Preoxidized Condition | | **IEC** | IEC 60404-8-6 | Metallic Magnetic Materials - Soft Magnetic Metallic Materials | | **UNS** | **K94600** | Unified Numbering System Designation | | **AMS** | AMS 7721 | Brazing Alloy, Iron-Nickel, 46Ni-54Fe | --- #### **6. Manufacturing & Processing Notes** * **Sealing Process:** Requires careful surface preparation and controlled atmosphere heating to approximately 1000°C for optimal glass wetting and bond formation * **Machining:** Can be machined using standard techniques; requires sharp tools and positive rake angles * **Heat Treatment:** Typically used in annealed condition; stress relief annealing at 650-750°C recommended after severe forming operations * **Surface Preparation:** Copper plating or controlled pre-oxidation often applied to enhance glass adherence --- **Summary** **Alloy 46 (UNS K94600) Tube** represents a specialized form of this matched sealing alloy, enabling the construction of cylindrical glass-to-metal seals for demanding electronic, optical, and industrial applications. Its precisely controlled thermal expansion properties, combined with excellent formability and consistent sealing performance, make it indispensable for applications requiring reliable hermetic encapsulation in tubular configurations. Compliance with **ASTM F15** and related standards ensures material consistency and performance reliability for critical sealing 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 2486 gallon liquid totes Special package is available on request.