Alloy 46,Glass sealing 46 Alloy Bar(Round bar, Flat bar),UNS K94600,E FORU

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

### **Alloy 46 (Glass Sealing 46) - Round Bar & Flat Bar Product Overview** **Alloy 46** is a precision iron-nickel alloy engineered for making matched coefficient of thermal expansion (CTE) seals with soft glass. Its primary function is to form strong, hermetic bonds that can withstand thermal cycling without cracking the glass or breaking the seal. The **Round Bar** and **Flat Bar** forms provide robust stock material for machining into various components used in electronic and hermetic packaging. * **UNS Designation:** **K94600** * **Common Product Forms:** Round Bar, Flat Bar (also known as Rectangular Bar), Wire, and Strip. --- #### **1. Chemical Composition** The chemical composition is tightly controlled to ensure consistent thermal and magnetic properties. | Element | Percentage (%) | Role in the Alloy | | :--- | :--- | :--- | | **Nickel (Ni)** | 45.0 - 47.0 | Defines the Curie point and the critical thermal expansion characteristics. | | **Iron (Fe)** | Balance | Forms the base of the alloy. | | **Manganese (Mn)** | 0.10 - 0.30 | Acts as a deoxidizer and improves hot workability. | | **Silicon (Si)** | 0.10 - 0.30 | Enhances scale resistance and improves the flow of glass during sealing. | | **Carbon (C)** | 0.05 max | Kept low to prevent embrittlement and maintain ductility. | | **Sulfur (S)** | 0.02 max | Impurity, minimized to prevent hot shortness. | | **Phosphorus (P)** | 0.02 max | Impurity, minimized to preserve ductility and formability. | --- #### **2. Physical Properties** The physical properties are characterized by a predictable thermal expansion curve that matches 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) | The temperature at which the alloy transitions from ferromagnetic to paramagnetic, causing a change in the CTE slope. | | **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) | Matches closely with soft glasses such as Corning 0080, 0120, 0010, and others in the 9000 series. | | **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 non-magnetic above the Curie point, which is important for some applications. | --- #### **3. Mechanical Properties (Typical - Annealed Condition)** Bars are typically supplied in the annealed state to facilitate machining and cold forming. * **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 * **Machinability:** ~40% (compared to Free-Cutting Brass at 100%). Requires positive rake angles and sharp tools. --- #### **4. Product Forms & Specific Applications** **Glass Sealing 46 Alloy Bar (Round & Flat)** * **Description:** **Round Bars** and **Flat Bars** are supplied as mill stock for downstream machining and fabrication. They offer a versatile form factor for producing custom components. The surface is often clean and descaled, and may be copper-plated to prevent oxidation and improve glass wetting. * **Primary Applications:** * **Machined Headers and Stems:** Round bars are used to machine larger components like tube stems, header disks, and connector bodies where a glass seal is formed directly into a precision-machined metal part. * **Support Rods and Structural Pins:** Flat and round bars are used for internal structural supports, anode/cathode mounts, and heavy-duty lead-in pins in larger electronic envelopes (e.g., power tubes, microwave tubes, X-ray tubes). * **Hermetic Feedthroughs:** Machined from bar stock to create multi-pin connectors or custom-shaped feedthroughs for aerospace, military, and high-reliability industrial applications. * **Glass-to-Metal Seal Flanges:** Flat bar can be processed into custom flanges used to seal glass windows or viewports to metal chambers. --- #### **5. International Standards** Alloy 46 / UNS K94600 is specified in several key international standards. | Standard Type | Standard Number | Title / Specification | | :--- | :--- | :--- | | **ASTM** | **ASTM F15** | *Standard Specification for Iron-Nickel Sealing Alloys* (This is the primary specification for bar forms). | | **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) Round Bar and Flat Bar** provide essential raw material for manufacturing robust, high-integrity glass-to-metal seal components. Their precisely matched thermal expansion with soft glass, combined with good machinability in the annealed condition, makes them indispensable in the production of vacuum tubes, hermetic connectors, and various high-reliability electronic enclosures. Compliance with standards like **ASTM F15** guarantees the material quality and consistency required for these critical 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 2484 gallon liquid totes Special package is available on request.