Elektron QE22 Magnesium Casting Alloy, UNS M18220,E FOUR

**Elektron QE22 Magnesium Casting Alloy (UNS M18220)** **Product Overview** Elektron QE22 is a high-strength, heat-treatable magnesium casting alloy renowned for its excellent room temperature strength and good creep resistance at elevated temperatures up to approximately **250°C (482°F)**. As part of the magnesium-silver-rare earth (Mg-Ag-RE) family, it leverages a combination of silver (Ag) and rare earth elements to achieve a superior combination of tensile strength, yield strength, and castability for critical aerospace components. For many years, it has been a benchmark high-performance casting alloy in the aerospace industry. This alloy is typically used in sand, permanent mold, and investment casting processes to manufacture complex, high-integrity components. --- #### **1. Chemical Composition** The composition of Elektron QE22 is precisely controlled to achieve its peak mechanical properties through heat treatment. | Element | Composition (% by Weight) | | :--- | :--- | | **Silver (Ag)** | 2.0 - 3.0 % | | **Rare Earths (RE)*** | 1.8 - 2.5 % | | **Zirconium (Zr)** | 0.4 - 1.0 % | | **Zinc (Zn)** | ≤ 0.2 % | | **Manganese (Mn)** | ≤ 0.3 % | | **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" are typically a blend of Neodymium (Nd) and Gadolinium (Gd). **Silver (Ag)** is a critical alloying element that significantly enhances the age-hardening response, leading to high strength and improved creep resistance. **Zirconium (Zr)** acts as a powerful grain refiner. --- #### **2. Physical & Mechanical Properties** Elektron QE22 exhibits an outstanding property profile, particularly after a full T6 heat treatment (solution heat treatment and aging). **Physical Properties:** * **Density:** ~1.82 g/cm³ (0.065 lb/in³) - Maintains the exceptional lightweight advantage of magnesium. * **Melting Range:** ~ 545 - 640 °C (1013 - 1184 °F) **Typical Mechanical Properties (at Room Temperature, T6 Condition):** * **Ultimate Tensile Strength (UTS):** 250 - 265 MPa (36 - 38 ksi) * **Tensile Yield Strength (TYS):** 185 - 200 MPa (27 - 29 ksi) * **Elongation:** 2 - 5% * **Shear Strength:** ~ 125 MPa (18 ksi) * **Hardness:** 70 - 80 HBW **Elevated Temperature Performance:** QE22 retains useful mechanical properties at elevated temperatures, which is a key reason for its selection in aerospace applications. * **Creep Resistance:** Good resistance up to **250°C (482°F)**. * **Strength at 200°C (392°F):** Retains a high percentage of its yield strength, outperforming many other casting alloys. --- #### **3. International Standards & Specifications** Elektron QE22 is covered by several key international and aerospace standards. * **Unified Numbering System (UNS):** **UNS M18220** * **Aerospace Material Specification (AMS):** **AMS 4418** (This is the primary specification for sand castings of this alloy) * **ASTM International:** **ASTM B80** (Referenced for sand casting specifications) * **Proprietary Designation:** **Elektron QE22** is a registered trademark of Luxfer MEL Technologies. --- #### **4. Product Applications** Due to its high strength and elevated temperature capability, QE22 is predominantly used in the most demanding aerospace and defense applications. * **Aerospace & Gas Turbine Engines:** * **Engine Casings:** Compressor and intermediate casings, gearbox housings. * **Transmission Housings:** Accessory drive housings within the engine core. * **Engine Mounts and Brackets:** Critical structural components subjected to high loads and temperatures. * **Defense and Aerospace:** * Components for missile systems, radar antenna structures, and communication equipment housings. * **Racing & High-Performance Applications:** * **Motorsports:** Gearbox casings and other powertrain components in Formula 1 and other elite racing series where weight and strength are paramount. --- **Summary** **Elektron QE22 (UNS M18220)** is a premium, high-strength magnesium casting alloy that has set a long-standing performance standard in the aerospace industry. Its unique chemistry, centered on **silver and rare earth elements**, provides an exceptional combination of high tensile and yield strength at room temperature, coupled with good creep resistance up to **250°C**. Governed by stringent standards like **AMS 4418**, it remains a trusted material for critical, weight-sensitive components in gas turbine engines and other high-stress aerospace applications, where its performance justifies its premium cost.

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 3392 gallon liquid totes Special package is available on request.