Alloy 45,Low expansion 45 Alloy,,E FORU

### **Alloy 45 / Low Expansion 45 Alloy** **Iron-Nickel Controlled Expansion Alloy for Glass and Ceramic Sealing** --- #### **1. Overview** **Low Expansion 45 Alloy**, commercially designated as **Alloy 45**, is an iron-nickel alloy specifically formulated to provide thermal expansion characteristics that closely match specific types of soda-lime and lead glasses. This controlled expansion behavior makes it particularly suitable for applications requiring reliable glass-to-metal seals where thermal stress management is critical. The alloy's composition is optimized to ensure compatibility with common sealing glasses while maintaining good mechanical properties and manufacturability. --- #### **2. Chemical Composition (Weight %)** The typical chemical composition of Alloy 45 is outlined below. The balance is Iron (Fe). | Element | Content (%) | Key Function | | :--- | :--- | :--- | | **Iron (Fe)** | Balance | Forms the primary matrix of the alloy system. | | **Nickel (Ni)** | 44.5 - 45.5 | Primary element controlling thermal expansion to match specific glass types. | | **Manganese (Mn)** | 0.30 - 0.60 | Enhances hot workability and acts as a deoxidizer during processing. | | **Silicon (Si)** | 0.15 - 0.25 | Improves fluidity during manufacturing and enhances oxidation resistance. | | **Carbon (C)** | 0.05 max | Carefully controlled to prevent gas formation during sealing processes. | | **Chromium (Cr)** | 0.15 max | Controlled impurity element. | | **Cobalt (Co)** | 0.15 max | Controlled impurity element. | | **Copper (Cu)** | 0.15 max | Controlled impurity element. | | **Aluminum (Al)** | 0.05 max | Regulated to ensure proper surface characteristics for glass bonding. | | **Sulfur (S)** | 0.015 max | Minimized to prevent hot shortness during fabrication. | | **Phosphorus (P)** | 0.015 max | Controlled to maintain material ductility and workability. | --- #### **3. Physical Properties** | Property | Value / Condition | | :--- | :--- | | **Density** | 8.17 g/cm³ (0.295 lb/in³) | | **Melting Point** | ~ 1425 °C (2597 °F) | | **Mean Coefficient of Thermal Expansion** | 20 - 300°C (68 - 572°F): **7.5 x 10⁻⁶/°C** (4.2 x 10⁻⁶/°F)
20 - 400°C (68 - 752°F): **8.8 x 10⁻⁶/°C** (4.9 x 10⁻⁶/°F)
20 - 450°C (68 - 842°F): **9.4 x 10⁻⁶/°C** (5.2 x 10⁻⁶/°F) | | **Thermal Conductivity** | 15.2 W/m·K (105 Btu·in/hr·ft²·°F) at 20°C (68°F) | | **Specific Heat Capacity** | 510 J/kg·K (0.122 Btu/lb·°F) at 20°C (68°F) | | **Electrical Resistivity** | 0.65 μΩ·m at 20°C (68°F) | | **Modulus of Elasticity (Young's Modulus)** | 148 GPa (21.5 x 10⁶ psi) at 20°C (68°F) | | **Curie Temperature** | ~ 440 °C (824 °F) | | **Magnetic Properties** | Ferromagnetic below Curie temperature | --- #### **4. Mechanical Properties (Typical for Annealed Condition)** | Property | Value at Room Temperature | | :--- | :--- | | **Tensile Strength** | 540 MPa (78 ksi) | | **Yield Strength (0.2% Offset)** | 370 MPa (54 ksi) | | **Elongation (in 50 mm / 2 in)** | 28% | | **Reduction of Area** | 62% | | **Hardness (Rockwell B)** | 80 HRB | | **Vickers Hardness** | 165 HV | --- #### **5. International Standards** Alloy 45 conforms to the following international specifications: * **ASTM:** * **F2560:** Standard Specification for 45Ni-55Fe Alloy (Alloy 45) Sealing Glass * **AMS:** * **AMS 7722:** Sheet, Strip, and Plate * **ISO:** * **ISO 19960:** Iron-nickel low expansion alloys * **JIS:** * **JIS C 2531:** Iron-nickel alloy for sealing use * **EN:** * **EN 10140:** Cold rolled narrow steel strip --- #### **6. Product Applications** Alloy 45 is extensively used in applications requiring matched thermal expansion with specific glass types: * **Lighting Industry:** * Incandescent and halogen lamp bases * Fluorescent lamp end caps * High-intensity discharge lamp seals * Specialty lighting components * **Electronics Packaging:** * Glass terminal seals * Feedthrough connectors * Hermetic electronic enclosures * Sensor packaging * **Automotive Components:** * Headlight and taillight assemblies * Instrument panel lighting * Control module seals * Sensor housings * **Consumer Electronics:** * Display panel seals * Indicator light assemblies * Appliance lighting components * Control panel windows * **Industrial Equipment:** * Gauge and instrument windows * Sight glass assemblies * Process viewing ports * Control panel components --- #### **7. Key Characteristics & Advantages** * **Optimized Thermal Expansion:** CTE of 7.5-9.4 x 10⁻⁶/°C closely matches soda-lime and lead glasses * **Excellent Glass Sealing Capability:** Forms strong, reliable bonds with common sealing glasses * **Good Mechanical Strength:** Provides structural support while maintaining seal integrity * **Thermal Cycle Resistance:** Withstands repeated heating and cooling without seal failure * **Good Electrical Conductivity:** Suitable for applications requiring electrical feedthroughs * **Excellent Fabricability:** Can be easily stamped, drawn, and formed into complex shapes * **Cost-Effective Performance:** Provides reliable sealing at competitive material cost * **Proven Reliability:** Long history of successful application in lighting and electronic industries --- **Disclaimer:** *The values provided are typical and for informational purposes only. For critical applications, always consult the official material data sheets from the supplier and relevant design codes. Proper surface preparation and controlled oxidation are essential for achieving optimal glass-to-metal seals.*

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 1687 gallon liquid totes Special package is available on request.