Elektron 21 Magnesium Casting Alloy，UNS M12310; AMS 4429,E FOUR

### **Product Datasheet: Elektron 21 Magnesium Casting Alloy (UNS M12310)** **High-Performance Rare Earth Magnesium Alloy for Aerospace Applications** --- #### **1. Overview** Elektron 21 (UNS M12310) is a premium magnesium casting alloy developed for high-performance aerospace and motorsport applications. Conforming to AMS 4429 specifications, this rare earth-containing alloy offers an exceptional combination of high-temperature strength, excellent castability, and superior corrosion resistance. Elektron 21 maintains mechanical properties at elevated temperatures up to 250°C (482°F), making it ideal for critical components operating in demanding thermal environments. --- #### **2. Key Features & Advantages** - **Excellent High-Temperature Performance:** Maintains strength up to 250°C (482°F) - **Superior Castability:** Produces sound, dense castings with minimal porosity - **Outstanding Corrosion Resistance:** Significantly better than conventional magnesium alloys - **Good Weldability and Repairability:** Suitable for TIG welding and repair - **Excellent Strength-to-Weight Ratio:** 35% lighter than aluminum alloys - **Low Thermal Expansion:** Good dimensional stability at elevated temperatures - **Proven Aerospace Heritage:** Extensive use in critical aircraft components --- #### **3. Chemical Composition (Weight %)** As specified in AMS 4429: | Element | Magnesium (Balance) | Rare Earth (RE) | Zinc | Zirconium | Other Elements (max) | |---------------|---------------------|-----------------|--------------|--------------|---------------------| | **Content (%)** | - | 2.5-4.0 | 0.20-0.50 | 0.4-1.0 | 0.30 total | *Note: Rare earth elements (primarily neodymium and praseodymium) provide solid solution strengthening and enhance high-temperature stability, while zirconium ensures fine grain structure.* --- #### **4. Typical Physical & Mechanical Properties** **Physical Properties:** | Property | Value | |---------------------------|------------------------------| | **Density** | 1.80 g/cm³ (0.065 lb/in³) | | **Melting Range** | 550-640°C (1022-1184°F) | | **Thermal Conductivity** | 70 W/m·K | | **Specific Heat Capacity**| 1050 J/kg·K | | **Coefficient of Thermal Expansion** | 25.5 × 10⁻⁶/°C | | **Electrical Resistivity**| 11.5 μΩ·cm | **Mechanical Properties (Sand Cast - Typical):** | Property | Room Temperature | 200°C (392°F) | 250°C (482°F) | |---------------------------|------------------------|------------------------|------------------------| | **Ultimate Tensile Strength** | 240 MPa (35 ksi) | 180 MPa (26 ksi) | 150 MPa (22 ksi) | | **Tensile Yield Strength**| 155 MPa (22 ksi) | 130 MPa (19 ksi) | 110 MPa (16 ksi) | | **Elongation** | 8% | 12% | 15% | | **Compressive Yield Strength** | 155 MPa (22 ksi) | 130 MPa (19 ksi) | 110 MPa (16 ksi) | | **Shear Strength** | 140 MPa (20 ksi) | 110 MPa (16 ksi) | 90 MPa (13 ksi) | | **Fatigue Strength** | 110 MPa (16 ksi) | 85 MPa (12 ksi) | 70 MPa (10 ksi) | | **Elastic Modulus** | 45 GPa (6.5×10⁶ psi) | 42 GPa (6.1×10⁶ psi) | 40 GPa (5.8×10⁶ psi) | | **Hardness** | 65 HB | 55 HB | 45 HB | --- #### **5. International Standards & Specifications** Elektron 21 complies with the following standards: - **AMS 4429:** Aerospace Material Specification - **UNS M12310:** Unified Numbering System - **ASTM B80:** Standard Specification for Magnesium-Alloy Sand Castings - **ISO 16220:** Magnesium and magnesium alloys - Castings - **Proprietary Specifications:** Various OEM-specific standards --- #### **6. Applications** **Aerospace & Defense:** - Aircraft gearbox and transmission housings - Helicopter transmission casings - Auxiliary Power Unit (APU) components - Engine accessory housings and brackets - Missile and UAV structural components - Satellite housing and support structures **Motorsport & High-Performance Automotive:** - Formula One gearbox casings - Racing engine blocks and components - High-performance transmission cases - Motorcycle engine casings - Sports car structural components **Industrial & Specialized Applications:** - High-speed compressor housings - Industrial robot components - Nuclear instrumentation housings - Medical equipment components - Specialized machinery parts --- #### **7. Foundry & Processing Parameters** **Casting Characteristics:** - **Pouring Temperature:** 720-780°C (1328-1436°F) - **Mold Temperature:** 200-400°C (392-752°F) - **Fluidity:** Excellent for thin sections and complex geometries - **Feeding Requirements:** Moderate - **Hot Tearing Resistance:** Very good **Heat Treatment Options:** - **T5 Temper:** Artificial aging at 200°C (392°F) for 16 hours - **T6 Temper:** Solution treatment + artificial aging available - **Stress Relieving:** 250°C (482°F) for 2-4 hours **Machining Characteristics:** - **Machinability:** Excellent - better than most aluminum alloys - **Cutting Speed:** High-speed operations possible - **Surface Finish:** Very good to excellent - **Tool Life:** Extended compared to ferrous materials **Joining & Repair:** - **TIG Welding:** Excellent with proper filler material - **Repair Welding:** Suitable for casting repair - **Adhesive Bonding:** Good with proper surface preparation --- #### **8. Quality Assurance & Certification** - **Chemical Analysis:** Certified to AMS 4429 requirements - **Mechanical Testing:** From separately cast test bars - **Radiographic Inspection:** Capable of Level 1 quality - **Dye Penetrant Testing:** Standard surface inspection - **Microstructural Control:** Grain size and phase distribution - **Full Traceability:** From raw material to finished casting --- **Disclaimer** This technical data is based on typical properties for Elektron 21 magnesium alloy. Actual properties may vary depending on foundry practice, section size, and heat treatment parameters. The alloy is specifically designed for critical aerospace applications and requires strict process controls and certification. Users should consult AMS 4429 and conduct appropriate testing for specific applications. All processing must follow established aerospace quality procedures and magnesium safety protocols.

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 3386 gallon liquid totes Special package is available on request.