Elektron W28 Magnesium Alloy， Elektron 21 (EV31),E FOUR

### **Elektron W28 / Elektron 21 (EV31A) Magnesium Alloy** **Product Overview** Elektron W28, commercially designated as Elektron 21 or EV31A, is a high-performance magnesium-rare earth-zirconium casting alloy specifically developed for applications requiring excellent corrosion resistance combined with good mechanical properties and castability. As part of the advanced Mg-RE-Zr system, EV31A offers a superior combination of strength, corrosion resistance, and elevated temperature performance up to 250°C, making it particularly suitable for aerospace, defense, and automotive applications where reliability in corrosive environments is critical. This alloy is typically supplied as sand castings, investment castings, and permanent mold castings, with optimal properties achieved through T6 heat treatment. --- #### **1. Chemical Composition** EV31A features a carefully balanced rare earth composition optimized for corrosion resistance and mechanical properties. | Element | Composition (% by Weight) | | :---------------- | :-------------------------------- | | **Rare Earths (RE)*** | 2.9 - 3.6 % | | **Zirconium (Zr)** | 0.4 - 1.0 % | | **Zinc (Zn)** | 0.20 - 0.50 % | | **Manganese (Mn)** | ≤ 0.08 % | | **Copper (Cu)** | ≤ 0.03 % | | **Iron (Fe)** | ≤ 0.03 % | | **Nickel (Ni)** | ≤ 0.003 % | | **Silicon (Si)** | ≤ 0.03 % | | **Other Impurities** | ≤ 0.30 % (each) | | **Magnesium (Mg)** | Balance | *Note:* The "Rare Earths" primarily consist of neodymium (Nd) with controlled amounts of gadolinium (Gd) and dysprosium (Dy). **Zinc** enhances strength and corrosion resistance, while **zirconium** provides essential grain refinement. The specific rare earth combination is optimized for both mechanical properties and corrosion performance. --- #### **2. Physical & Mechanical Properties** EV31A offers a balanced combination of mechanical properties with excellent corrosion resistance. **Physical Properties:** * **Density:** 1.83 g/cm³ (0.066 lb/in³) * **Melting Range:** 550 - 640 °C (1022 - 1184 °F) * **Coefficient of Thermal Expansion:** 26.3 μm/m·°C (20-200°C) * **Thermal Conductivity:** 75 W/m·K * **Specific Heat Capacity:** 1050 J/kg·K **Typical Mechanical Properties (T6 Temper):** * **Ultimate Tensile Strength (UTS):** 230 - 250 MPa (33 - 36 ksi) * **Tensile Yield Strength (TYS):** 150 - 170 MPa (22 - 25 ksi) * **Elongation:** 4 - 6% * **Compressive Yield Strength:** 150 - 170 MPa (22 - 25 ksi) * **Shear Strength:** 135 - 155 MPa (20 - 22 ksi) * **Fatigue Strength:** 120 - 140 MPa (17 - 20 ksi) * **Hardness:** 70 - 80 HBW * **Modulus of Elasticity:** 45 GPa (6.5 × 10³ ksi) **Corrosion and Elevated Temperature Performance:** * **Exceptional salt spray corrosion resistance** (> 1000 hours to first corrosion) * **Good creep resistance up to 250°C (482°F)** * **Excellent stress corrosion cracking resistance** * **Superior general corrosion resistance** compared to most magnesium alloys --- #### **3. International Standards & Specifications** EV31A is recognized by major international standards organizations. * **Aerospace Material Specification (AMS):** **AMS 4428** * **ASTM International:** **ASTM B80 EV31A-T6** * **SAE International:** **SAE J465** * **UNS Designation:** **UNS M18330** * **European Standards:** **EN 1753** (Mg-RE-Zr) * **Military Standards:** **MIL-M-46098** * **Proprietary Designation:** **Elektron 21** / **EV31A** / **W28** (Luxfer MEL Technologies) --- #### **4. Product Applications** EV31A is widely used in applications requiring excellent corrosion resistance combined with good mechanical properties. * **Aerospace & Defense:** * **Aircraft Engine Accessory Housings** * **Gearbox and Transmission Casings** * **Helicopter Transmission Housings** * **Military Electronics Enclosures** * **Missile and Defense System Components** * **Automotive & Transportation:** * **High-Performance Engine Components** * **Racing Transmission Casings** * **Luxury Vehicle Components** * **Aerospace-Grade Automotive Parts** * **Industrial & Marine:** * **Marine Component Housings** * **Chemical Processing Equipment** * **Offshore Platform Components** * **Corrosion-Sensitive Industrial Equipment** * **Special Applications:** * **Formula 1 Components** * **High-Value Electronic Enclosures** * **Medical Equipment Housings** * **Communications Equipment** --- #### **5. Manufacturing Characteristics** **Casting Performance:** * Excellent castability with good fluidity * Low tendency for hot tearing * Suitable for complex geometries and thin walls * Good dimensional stability * Consistent mechanical properties **Secondary Processing:** * Good machinability with excellent surface finish * Excellent response to T6 heat treatment * Good weldability using TIG and MIG processes * Superior coating adhesion and paint compatibility * Excellent surface treatment response --- **Summary** **Elektron W28 / Elektron 21 (EV31A) Magnesium Alloy** represents a significant advancement in corrosion-resistant magnesium alloy technology, offering an exceptional balance of **mechanical properties**, **castability**, and **superior corrosion resistance**. The optimized **rare earth-zinc-zirconium** composition provides performance characteristics that make it suitable for the most demanding applications in corrosive environments. Certification to **AMS 4428** and **ASTM B80** ensures its reliability for critical aerospace and defense components where corrosion performance is as important as mechanical properties. EV31A's exceptional salt spray resistance, combined with good elevated temperature performance and excellent castability, makes it the material of choice for applications where conventional magnesium alloys would succumb to corrosive attack. The alloy continues to expand the application boundaries for magnesium in marine, aerospace, and industrial sectors, providing engineers with a lightweight solution that doesn't compromise on durability or service life in challenging environments.

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 3424 gallon liquid totes Special package is available on request.