Magnesium EA65RS-T4,E FOUR

### **Technical Datasheet: Magnesium Alloy EA65RS-T4** --- #### **1. Material Overview** EA65RS-T4 is a premium rare-earth magnesium alloy supplied in the solution heat-treated condition. The **"T4"** temper indicates the material has undergone **solution heat treatment followed by natural aging**, providing an optimal balance of high strength, excellent ductility, and superior corrosion resistance. The "RS" designation represents a specialized rare-earth composition optimized for enhanced mechanical properties and improved manufacturing characteristics. --- #### **2. Key Features** - **Exceptional combination of strength and ductility** - **Superior corrosion resistance** - **Excellent castability with minimal hot tearing** - **Enhanced fatigue performance** - **Outstanding impact toughness** - **Good weldability and repair characteristics** --- #### **3. Chemical Composition (Weight %)** | Element | Composition (%) | |---------|-----------------| | **Rare Earths (RE)** | 5.8–6.5% | | **Silver (Ag)** | 2.2–3.0% | | **Zirconium (Zr)** | 0.5–1.0% | | **Zinc (Zn)** | 0.2–0.7% | | **Manganese (Mn)** | ≤ 0.25% | | **Silicon (Si)** | ≤ 0.05% | | **Copper (Cu)** | ≤ 0.05% | | **Iron (Fe)** | ≤ 0.01% | | **Nickel (Ni)** | ≤ 0.005% | | **Other Elements** | ≤ 0.30% | | **Magnesium (Mg)** | Balance | *Note: The specific rare earth composition includes yttrium and heavy rare earth elements that provide unique strengthening mechanisms and exceptional corrosion resistance properties.* --- #### **4. Mechanical Properties (T4 Temper)** | Property | Value (Metric) | Value (Imperial) | |----------|----------------|------------------| | **Ultimate Tensile Strength** | 260–300 MPa | 38–44 ksi | | **Tensile Yield Strength (0.2%)** | 160–190 MPa | 23–28 ksi | | **Elongation (% in 50mm)** | 8–12% | 8–12% | | **Compressive Yield Strength** | 160–190 MPa | 23–28 ksi | | **Hardness (Brinell)** | 70–80 HB | 70–80 HB | | **Shear Strength** | 150–170 MPa | 22–25 ksi | | **Fatigue Strength** | 120–140 MPa | 17–20 ksi | | **Impact Toughness (Charpy)** | 14–20 J | 10–15 ft-lb | | **Modulus of Elasticity** | 44.5 GPa | 6.45×10⁶ psi | | **Poisson's Ratio** | 0.35 | 0.35 | --- #### **5. Physical Properties** | Property | Value | |----------|-------| | **Density** | 1.85 g/cm³ | | **Melting Range** | 545–640°C | | **Specific Heat** | 1.01 kJ/kg·K | | **Thermal Conductivity** | 96 W/m·K | | **Coefficient of Thermal Expansion** | 26.3 μm/m·K | | **Electrical Resistivity** | 82 nΩ·m | --- #### **6. Heat Treatment Cycle (T4)** - **Solution Treatment:** 525°C ± 5°C for 10–16 hours - **Quenching Medium:** Hot water (65–95°C) - **Natural Aging Period:** 30–60 days at room temperature - **Microstructure:** Homogeneous supersaturated solid solution --- #### **7. Applicable Standards** - **ASTM International:** - **ASTM B80** – Standard Specification for Magnesium-Alloy Sand Castings - **ASTM B199** – Standard Specification for Magnesium-Alloy Permanent Mold Castings - **Aerospace Standards:** - **AMS 4431** – Magnesium Alloy Castings - **BAC 5731** – Boeing Material Specification - **European Standards:** - **EN 1753** – Magnesium and magnesium alloys - **International Standards:** - **ISO 16220** – Magnesium and magnesium alloys --- #### **8. Manufacturing Characteristics** - **Casting Methods:** Excellent for sand, permanent mold, and investment casting - **Optimal Pouring Temperature:** 715–765°C - **Fluidity Rating:** Excellent - **Hot Tearing Resistance:** Superior - **Machinability:** Excellent (high speed capabilities) - **Weldability:** Very good (TIG recommended with proper filler) --- #### **9. Applications** - **Aerospace Structures:** - Critical aircraft structural components - Helicopter transmission housings - Spacecraft structural members - Jet engine accessory components - **Defense Systems:** - Lightweight armor systems - Military aircraft components - Missile structural components - Portable military equipment - **High-Performance Automotive:** - Racing engine blocks and components - High-stress suspension parts - Performance transmission cases - **Specialized Industrial:** - Nuclear applications - Medical imaging equipment - High-value instrument frames - Robotics components --- #### **10. Corrosion Performance & Protection** - **Salt Spray Resistance:** >700 hours to initial corrosion - **Stress Corrosion Cracking:** Excellent resistance - **Galvanic Corrosion:** Requires standard isolation practices - **Coating Compatibility:** Excellent with all standard magnesium coatings --- #### **11. Design Guidelines** - **Maximum Service Temperature:** 250°C continuous - **Recommended Section Thickness:** 3–120 mm - **Fatigue Design:** Excellent for high-cycle fatigue applications - **Damage Tolerance:** Superior due to high toughness --- #### **12. Comparison with Similar Alloys** - **vs. EA65RS-T6:** Better ductility and impact strength - **vs. WE43-T4:** Superior mechanical properties - **vs. Conventional Mg-RE Alloys:** Better combination of properties --- **Note:** EA65RS-T4 represents the premium category of solution-treated magnesium-rare earth alloys, offering an exceptional balance of mechanical properties suitable for the most demanding structural applications. The T4 condition provides maximum toughness and damage tolerance, making it particularly valuable in aerospace and defense applications where reliability is critical. Always consult with materials engineering specialists for application-specific recommendations and conduct thorough qualification testing for critical applications.

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 3329 gallon liquid totes Special package is available on request.