Alloy 48,Nilo 48,UNS K94800,E FORU

### **Alloy 48 / Nilo 48 / UNS K94800** **Iron-Nickel Controlled Expansion Alloy for Precision Electronic Applications** --- #### **1. Overview** **Nilo 48**, commercially designated as **Alloy 48**, is an iron-nickel alloy specifically engineered to provide thermal expansion characteristics that bridge the gap between lower nickel alloys like Alloy 42 and higher nickel content alloys. This carefully balanced composition offers optimized thermal expansion matching for specific electronic and sealing applications, particularly where compatibility with certain ceramic substrates and specialized glasses is required. The alloy demonstrates excellent stability and reliability in precision electronic packaging. --- #### **2. Chemical Composition (Weight %)** The typical chemical composition of Alloy 48 is outlined below. The balance is Iron (Fe). | Element | Content (%) | Key Function | | :--- | :--- | :--- | | **Iron (Fe)** | Balance | Forms the fundamental matrix of the alloy system. | | **Nickel (Ni)** | 47.5 - 48.5 | Primary element controlling thermal expansion characteristics. | | **Manganese (Mn)** | 0.30 - 0.60 | Enhances hot workability and acts as a deoxidizer during manufacturing. | | **Silicon (Si)** | 0.15 - 0.25 | Improves oxidation resistance and surface characteristics. | | **Carbon (C)** | 0.03 max | Minimized to prevent gas formation and ensure sealing integrity. | | **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 | Carefully regulated to ensure proper surface properties for bonding. | | **Titanium (Ti)** | 0.05 max | Controlled trace element. | | **Sulfur (S)** | 0.010 max | Minimized to prevent hot shortness during processing. | | **Phosphorus (P)** | 0.010 max | Controlled to maintain material ductility. | --- #### **3. Physical Properties** | Property | Value / Condition | | :--- | :--- | | **Density** | 8.19 g/cm³ (0.296 lb/in³) | | **Melting Point** | ~ 1420 °C (2588 °F) | | **Mean Coefficient of Thermal Expansion** | 20 - 300°C (68 - 572°F): **8.8 x 10⁻⁶/°C** (4.9 x 10⁻⁶/°F)
20 - 400°C (68 - 752°F): **9.6 x 10⁻⁶/°C** (5.3 x 10⁻⁶/°F)
20 - 450°C (68 - 842°F): **10.1 x 10⁻⁶/°C** (5.6 x 10⁻⁶/°F) | | **Thermal Conductivity** | 15.8 W/m·K (109 Btu·in/hr·ft²·°F) at 20°C (68°F) | | **Specific Heat Capacity** | 505 J/kg·K (0.121 Btu/lb·°F) at 20°C (68°F) | | **Electrical Resistivity** | 0.60 μΩ·m at 20°C (68°F) | | **Modulus of Elasticity (Young's Modulus)** | 152 GPa (22.0 x 10⁶ psi) at 20°C (68°F) | | **Curie Temperature** | ~ 500 °C (932 °F) | | **Magnetic Properties** | Ferromagnetic below Curie temperature | --- #### **4. Mechanical Properties (Typical for Annealed Condition)** | Property | Value at Room Temperature | | :--- | :--- | | **Tensile Strength** | 560 MPa (81 ksi) | | **Yield Strength (0.2% Offset)** | 390 MPa (57 ksi) | | **Elongation (in 50 mm / 2 in)** | 25% | | **Reduction of Area** | 58% | | **Hardness (Rockwell B)** | 84 HRB | | **Vickers Hardness** | 175 HV | --- #### **5. International Standards** Alloy 48 conforms to the following international specifications: * **ASTM:** * **F30:** Standard Specification for Iron-Nickel Sealing Alloys * **AMS:** * **AMS 7724:** Sheet, Strip, and Plate * **UNS:** K94800 * **ISO:** * **ISO 19960:** Iron-nickel low expansion alloys * **JIS:** * **JIS C 2531:** Iron-nickel alloy for sealing use * **IEC:** * **IEC 60680:** Test methods of glass-to-metal sealing --- #### **6. Product Applications** Alloy 48 serves critical functions in precision electronic and specialized sealing applications: * **Advanced Electronic Packaging:** * High-frequency device packages * Microwave circuit carriers * RF component housings * Semiconductor power devices * **Telecommunications:** * Fiber optic component seals * Base station electronics * Network infrastructure devices * Communication module packages * **Automotive Electronics:** * Advanced driver assistance systems * Power control units * Sensor packaging * Electric vehicle power electronics * **Medical Electronics:** * Diagnostic imaging components * Medical sensor housings * Therapeutic device packages * Patient monitoring equipment * **Industrial Controls:** * Process instrumentation * Control system enclosures * Industrial sensor packages * Automation system components --- #### **7. Key Characteristics & Advantages** * **Optimized Thermal Expansion:** CTE of 8.8-10.1 x 10⁻⁶/°C provides ideal matching for specific electronic applications * **Excellent Sealing Performance:** Reliable performance in glass and ceramic sealing applications * **Superior Thermal Stability:** Maintains dimensional stability across operating temperature ranges * **Good Mechanical Properties:** Balanced strength and formability for electronic components * **Enhanced Electrical Conductivity:** Improved conductivity compared to lower nickel alloys * **Excellent Manufacturing Characteristics:** Suitable for precision stamping and forming processes * **Consistent Performance:** Reliable and repeatable material properties * **Proven Reliability:** Successful implementation in demanding electronic applications --- **Disclaimer:** *Nilo® is a registered trademark. 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 processing and surface preparation are essential for achieving optimal performance in specific 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 1689 gallon liquid totes Special package is available on request.