Permalloy, Other/Similar Specs,,E FORU

British Specs:，American Specs:MIL-N-14411 C ASTM A753，German Specs:

### **Product Introduction: Permalloy & Similar High-Performance Nickel-Iron Alloys** **Permalloy** is the trademarked name for a family of nickel-iron alloys renowned for their exceptional soft magnetic properties, primarily high magnetic permeability and low coercivity. While "Permalloy" often refers to the 80% Nickel-20% Iron composition, the term broadly encompasses a range of alloys with tailored properties achieved by varying the nickel content and adding elements like Molybdenum, Copper, and Chromium. This document provides an overview of key alloys within this family, including their chemical compositions, physical properties, and the international standards that govern them. Understanding these "Other/Similar Specs" is crucial for selecting the optimal material for specific magnetic and electrical applications. --- #### **1. Chemical Composition & Alloy Variants** The properties of these alloys are highly dependent on their precise chemical composition. The following table outlines the most common variants. **Typical Chemical Composition (Weight %):** | Alloy Name / Common Designation | Ni (Nickel) | Fe (Iron) | Mo (Molybdenum) | Cu (Copper) | Cr (Chromium) | Mn (Manganese) | Other | | :--- | :---: | :---: | :---: | :---: | :---: | :---: | :---: | | **Permalloy 80 (80Ni-20Fe)** | 78.0 - 81.0 | Balance | - | - | - | 0.30 - 0.60 | - | | **Molybdenum-Permalloy (e.g., 79Ni-17Fe-4Mo)** | 78.0 - 81.0 | Balance | 3.90 - 4.50 | - | - | 0.30 - 0.60 | - | | **Superpermalloy (79Ni-16Fe-5Mo)** | ~79 | Balance | ~5 | - | - | - | - | | **Mumetal® (77Ni-16Fe-5Cu-2Cr)** | ~77 | Balance | - | ~5 | ~2 | - | - | | **Hiperco® / Permendur (50Fe-50Co)** | - | ~50 | - | - | - | - | **Co: 49** | | **45 Permalloy (45Ni-55Fe)** | 44.0 - 46.0 | Balance | - | - | - | 0.30 - 0.60 | - | **Key Differentiators:** * **Permalloy 80 & Mo-Permalloy:** The benchmark for high permeability and low core loss. * **Superpermalloy:** Offers the highest initial and maximum permeability of the group. * **Mumetal®:** Excellent magnetic shielding properties, especially at low field strengths; known for its high initial permeability. * **Hiperco® / Permendur:** Distinguished by its very high saturation induction (~2.4 T), making it suitable for high-flensity applications like aerospace motors and transformers. It is a cobalt-iron alloy, not a nickel-iron one, but is a key "similar spec" in high-performance soft magnetics. * **45 Permalloy:** A lower nickel content results in higher saturation induction than 80% Ni alloys but with lower permeability. --- #### **2. Physical & Magnetic Properties (Comparative Overview)** Properties are highly dependent on heat treatment and final processing (e.g., cold rolling, annealing). The values below are typical for annealed strip. | Property | Permalloy 80 | Mo-Permalloy | Superpermalloy | Mumetal® | Hiperco® 50 | 45 Permalloy | | :--- | :---: | :---: | :---: | :---: | :---: | :---: | | **Initial Permeability (μᵢ)** | 20,000 - 50,000 | 30,000 - 60,000 | 50,000 - 150,000 | 40,000 - 100,000 | 800 - 2,000 | 2,500 - 5,000 | | **Max. Permeability (μₘₐₓ)** | 70,000 - 150,000 | 100,000 - 200,000 | 200,000 - 1,000,000 | 200,000 - 400,000 | 5,000 - 10,000 | 25,000 - 50,000 | | **Coercivity (Hc) [A/m]** | 1.5 - 4.0 | 1.0 - 2.0 | 0.2 - 0.8 | 0.5 - 2.0 | 40 - 100 | 8 - 20 | | **Saturation Induction (Bs) [T]** | 0.65 - 0.82 | 0.65 - 0.80 | 0.65 - 0.78 | 0.55 - 0.75 | **2.30 - 2.45** | 1.50 - 1.60 | | **Resistivity (μΩ·cm)** | 20 - 25 | 55 - 65 | 55 - 65 | 40 - 50 | 25 - 30 | 25 - 30 | | **Curie Temperature [°C]** | ~460 | ~460 | ~400 | ~360 | ~980 | ~440 | | **Density [g/cm³]** | 8.70 - 8.80 | 8.70 - 8.80 | 8.77 | 8.70 - 8.75 | 8.10 - 8.20 | 8.17 | --- #### **3. Product Applications** The choice of alloy is driven by the specific requirements of the application: * **Permalloy 80 / Mo-Permalloy / Superpermalloy:** * **Transformers & Inductors:** For high-performance, low-loss applications, especially in aerospace and military power supplies. * **Magnetic Shielding:** Sensitive electronic components, CRT displays, photomultiplier tubes. * **Recording Heads:** In older tape and disk drives. * **Current Sensors & Instrument Transformers.** * **Mumetal®:** * **Ultra-High Performance Shielding:** Primary choice for shielding very low-level magnetic fields, such as in MRI rooms, electron microscopes, and satellite instrumentation. * **Hiperco® / Permendur:** * **Aerospace Actuators & Motors:** Where high power-to-weight ratio is critical. * **High-Flux Density Transformer Cores.** * **Magnetic Bearings and High-Speed Rotors.** * **45 Permalloy:** * **DC Motors and Generators.** * **Magnetic Relays.** * **Transformers** requiring a good balance of saturation flux density and permeability. --- #### **4. International Standards** These alloys are covered by various international standards that specify their chemical, mechanical, and magnetic properties. * **ASTM (American Society for Testing and Materials):** * **ASTM A753 / A753M:** "Standard Specification for Nickel-Iron Soft Magnetic Alloys." This is the primary standard covering Types 1 through 8 (e.g., UNS N14080 for 80% Ni). * **ASTM A801:** "Standard Specification for Cobalt-Fe-V Soft Magnetic Alloys" (covers Permendur-type alloys like Hiperco). * **IEC (International Electrotechnical Commission):** * **IEC 60404-8-6:** "Magnetic materials - Part 8-6: Specifications for individual materials - Soft magnetic metallic materials." This standard provides detailed classifications for nickel-iron and cobalt-iron alloys. * **Military Standards (USA):** * **MIL-N-14411C:** Covers several compositions of nickel-iron core alloys. * **Other National Standards:** * **JIS C 2531 (Japanese Industrial Standards):** For resistance alloys and soft magnetic alloys. * **DIN 17470 (Deutsches Institut für Normung):** For precision alloys. --- #### **5. Selection Guide & Key Advantages** * **For Highest Permeability / Lowest Core Loss:** Choose **Superpermalloy** or **Molybdenum-Permalloy**. * **For Best Magnetic Shielding at Low Field Strengths:** Choose **Mumetal®**. * **For Highest Saturation Flux Density (High Power):** Choose **Hiperco® 50** (Cobalt-Iron). * **For a Balance of Saturation and Permeability at Lower Cost:** Choose **45 Permalloy**. **Our expertise allows us to supply these advanced alloys in various forms—including sheet, strip, bar, and custom forgings—and provide guidance on the optimal heat treatment to achieve your desired magnetic and mechanical properties.** **Contact us to discuss your application and select the perfect high-performance soft magnetic alloy for your needs.**

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 2557 gallon liquid totes Special package is available on request.