Alloy 39，Low Expansion 39 Alloy ，,E FORU

British Specs:，American Specs:，German Specs:

### **Product Introduction: Alloy 39 / Low Expansion 39 Alloy** **Premium Controlled Expansion Alloy for Precision Engineering Applications** **Alloy 39** is a advanced low expansion iron-nickel-cobalt alloy specifically engineered for applications requiring exceptional dimensional stability under varying temperature conditions. This specialized alloy offers an optimal balance of low thermal expansion characteristics, excellent mechanical properties, and superior manufacturability, making it the material of choice for precision instruments, electronic packaging, and aerospace components where thermal stability is critical. --- #### **1. Chemical Composition (Weight %)** | Element | Content (%) | Control Purpose | | :--- | :--- | :--- | | **Nickel (Ni)** | 38.0 - 40.0 | Primary expansion control | | **Cobalt (Co)** | 14.0 - 16.0 | Secondary expansion adjustment | | **Iron (Fe)** | Balance | Matrix formation | | **Manganese (Mn)** | 0.50 max | Deoxidation and sulfur control | | **Silicon (Si)** | 0.30 max | Deoxidation | | **Carbon (C)** | 0.05 max | Weldability and formability | | **Chromium (Cr)** | 0.20 max | Surface stability | | **Aluminum (Al)** | 0.10 max | Deoxidation | | **Copper (Cu)** | 0.20 max | Minor alloying element | | **Titanium (Ti)** | 0.10 max | Grain refinement | | **Sulfur (S)** | 0.015 max | Hot workability | | **Phosphorus (P)** | 0.015 max | Ductility preservation | * **Precision Formulation:** The carefully balanced nickel and cobalt content provides exceptional thermal expansion control, while minimal impurity levels ensure consistent performance and processing characteristics. --- #### **2. Physical Properties** | Property | Value | Condition | | :--- | :--- | :--- | | **Density** | 8.17 g/cm³ | 20°C | | **Melting Point** | 1450°C | Approximate | | **Thermal Conductivity** | 14.5 W/m·K | 20°C | | **Mean CTE (20-300°C)** | 4.5-5.5 × 10⁻⁶/°C | - | | **Specific Heat** | 460 J/kg·K | 20°C | | **Electrical Resistivity** | 75 μΩ·cm | 20°C | | **Curie Temperature** | 230°C | - | | **Magnetic Permeability** | < 1.05 | Annealed condition | --- #### **3. Mechanical Properties** | Property | Annealed Condition | Hard Temper | | :--- | :--- | :--- | | **Tensile Strength** | 70-85 ksi (483-586 MPa) | 95-115 ksi (655-793 MPa) | | **Yield Strength (0.2%)** | 40-55 ksi (276-379 MPa) | 85-105 ksi (586-724 MPa) | | **Elongation** | 30-40% | 12-20% | | **Hardness** | HRB 75-85 | HRB 90-100 | | **Modulus of Elasticity** | 22 × 10⁶ psi (152 GPa) | 22 × 10⁶ psi (152 GPa) | --- #### **4. Product Specifications & Applications** **Available Product Forms:** - Sheet and Strip: 0.001" to 0.125" thickness - Plate: 0.126" to 2.000" thickness - Bar and Rod: 0.125" to 6.000" diameter - Wire: 0.005" to 0.250" diameter - Custom Forgings and Fabricated Parts **Primary Applications:** * **Precision Instruments:** - Laser system components and mounts - Optical measuring equipment - Surveying instruments - Precision gauge blocks * **Electronics & Semiconductor:** - IC packaging substrates - Microwave package components - RF device housings - Semiconductor manufacturing equipment * **Aerospace & Defense:** - Gyroscope components - Inertial guidance systems - Satellite structures - Avionics packaging * **Scientific Research:** - Telescope components - Interferometer bases - Laboratory standards - Cryogenic equipment **Specialized Applications:** - Composite mold tools and fixtures - Precision measurement equipment - Frequency control devices - Energy sector instrumentation - Medical imaging equipment --- #### **5. International Standards & Specifications** **Global Standards Compliance:** - **ASTM F30:** Standard Specification for Iron-Nickel-Cobalt Alloys - **UNS K94670:** Unified Numbering System Designation - **AMS 7725:** Aerospace Material Specification - **MIL-DTL-23488:** Military Specification (Type IV) - **ISO 4950:** High yield strength steel plates - **DIN 17470:** German Industrial Standard - **JIS C2531:** Japanese Industrial Standard **Quality & Testing Standards:** - **ASTM E228:** Test Method for Linear Thermal Expansion - **ASTM E8:** Tension Testing of Metallic Materials - **ASTM E18:** Rockwell Hardness Testing - **ASTM E112:** Grain Size Determination --- #### **6. Technical Advantages & Processing Characteristics** **Key Performance Benefits:** - **Exceptional Dimensional Stability:** Minimal thermal expansion over wide temperature ranges - **Excellent Machinability:** Good tool life and surface finish achievable - **Superior Weldability:** Compatible with common welding techniques - **Good Corrosion Resistance:** Suitable for most industrial environments - **Controlled Magnetic Properties:** Low magnetic permeability **Manufacturing Considerations:** - **Heat Treatment:** Stress relieving at 425-540°C recommended after severe forming - **Machining:** Use sharp tools with positive rake angles for optimum results - **Cleaning:** Avoid chloride-containing solutions to prevent stress corrosion - **Forming:** Excellent cold working characteristics in annealed condition **Quality Assurance:** - **Chemical Analysis:** Ladle and product verification - **Mechanical Testing:** Full compliance with specification requirements - **Dimensional Inspection:** Precision measurement capabilities - **Non-Destructive Testing:** UT, RT, MT, PT as required - **Certification:** Full traceability with mill test reports --- #### **Why Choose Alloy 39?** * **Proven Reliability:** Extensive track record in critical applications * **Consistent Performance:** Tight control of thermal expansion properties * **Manufacturing Versatility:** Available in multiple product forms * **Technical Support:** Comprehensive application engineering assistance * **Quality Commitment:** Stringent quality control and certification * **Global Availability:** Worldwide distribution network **Industry Certifications:** - ISO 9001:2015 Quality Management System - AS9100 Aerospace Quality System - NADCAP accredited testing capabilities - OHSAS 18001 Health and Safety Management **Contact our technical team** for comprehensive technical data sheets, application assistance, and material selection guidance. Our experts are ready to provide solutions for your most demanding low expansion alloy requirements.

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 2755 gallon liquid totes Special package is available on request.