AZ91D Magnesium，UNS M11916; Mg; European EN 1753 MC 21120; ASTM B 94;SAE J465 (Ingot UNS M11917),E FOUR

Technical Datasheet: AZ91D Magnesium Alloy** **UNS M11916; UNS M11917 (Ingot); EN 1753 MC 21120; ASTM B94; SAE J465** --- #### **1. Material Overview** AZ91D is a high-purity magnesium-aluminum-zinc die-casting alloy, recognized as the industry standard for applications requiring an optimal balance of corrosion resistance, mechanical properties, and castability. It is supplied per multiple international standards in both finished casting (UNS M11916) and ingot (UNS M11917) forms. --- #### **2. Key Features** - **High corrosion resistance** due to strict control of Fe, Ni, and Cu impurities - **Excellent castability** with outstanding fluidity for thin and complex parts - **Lightweight** (~1.81 g/cm³), 35% lighter than aluminum - **Good strength-to-weight ratio** - **Excellent EMI/RFI shielding** properties - **Good machinability** --- #### **3. Chemical Composition (Weight %)** | Element | AZ91D (ASTM B94) | EN 1753 MC 21120 | |---------|------------------|------------------| | **Aluminum (Al)** | 8.3–9.7% | 8.5–9.5% | | **Zinc (Zn)** | 0.35–1.0% | 0.45–0.9% | | **Manganese (Mn)** | 0.15–0.50% | 0.17–0.40% | | **Silicon (Si)** | ≤ 0.20% | ≤ 0.10% | | **Copper (Cu)** | ≤ 0.030% | ≤ 0.025% | | **Iron (Fe)** | ≤ 0.005% | ≤ 0.004% | | **Nickel (Ni)** | ≤ 0.002% | ≤ 0.001% | | **Others (each)** | ≤ 0.02% | ≤ 0.01% | | **Magnesium (Mg)** | Balance | Balance | **Note:** The low Fe, Ni, and Cu content is critical for corrosion resistance. Fe/Mn ratio is carefully controlled. --- #### **4. Mechanical Properties (Typical, Die Cast Condition)** | Property | Value (Metric) | Value (Imperial) | |----------|----------------|------------------| | **Ultimate Tensile Strength** | 230–280 MPa | 33–41 ksi | | **Tensile Yield Strength (0.2%)** | 160–220 MPa | 23–32 ksi | | **Compressive Yield Strength** | 160–220 MPa | 23–32 ksi | | **Elongation (% in 50mm)** | 3–7% | 3–7% | | **Hardness (Brinell)** | 65–75 HB | 65–75 HB | | **Shear Strength** | 140–180 MPa | 20–26 ksi | | **Fatigue Strength** | 90–120 MPa | 13–17 ksi | | **Modulus of Elasticity** | 45 GPa | 6.5×10⁶ psi | | **Poisson’s Ratio** | 0.35 | 0.35 | --- #### **5. Physical Properties** | Property | Value | |----------|-------| | **Density** | 1.81 g/cm³ | | **Melting Range** | 470–595°C | | **Specific Heat** | 1.05 kJ/kg·K | | **Thermal Conductivity** | 72 W/m·K | | **Coefficient of Thermal Expansion** | 26 μm/m·K | | **Solidification Shrinkage** | 0.5–0.7% | --- #### **6. Applicable Standards** - **ASTM B94** – Standard Specification for Magnesium-Alloy Die Castings - **SAE J465** – Magnesium Alloy Ingot and Castings - **EN 1753** – Magnesium and magnesium alloys – MC 21120 - **UNS M11916** – Cast Products - **UNS M11917** – Ingot --- #### **7. Manufacturing & Processing** - **Die Casting Temperature:** 620–680°C - **Die Temperature:** 200–300°C - **Injection Speed:** 30–60 m/s - **Minimum Wall Thickness:** 1.0–1.5 mm - **Machinability:** Excellent (high speed, low power consumption) - **Surface Finish:** As-cast: 1.5–4.0 μm Ra --- #### **8. Applications** - **Automotive:** Transmission cases, steering wheels, intake manifolds, brackets - **Electronics:** Laptop and phone housings, camera bodies, projector frames - **Industrial:** Power tool housings, machinery covers, pneumatic tool bodies - **Aerospace & Defense:** Avionics enclosures, drone components, guidance system housings - **Consumer:** Sports equipment, luggage frames, household appliance parts --- #### **9. Corrosion Performance & Protection** - **Salt Spray Resistance:** >96 hours to initial red rust (ASTM B117) - **Recommended Coatings:** Chromate conversion, anodizing, powder coating, E-coat - **Galvanic Compatibility:** Isolate from more noble metals in corrosive environments --- #### **10. Design & Usage Notes** - Not recommended for prolonged use above 120°C - Avoid sharp corners and thick sections to minimize porosity - Use appropriate fasteners to prevent galvanic corrosion - Can be welded and repaired with TIG or MIG using compatible filler wire --- This datasheet is based on industry standards and typical manufacturer data. Properties may vary with processing parameters, section size, and heat treatment. Always refer to certified test reports for critical applications. AZ91D remains the most widely specified magnesium die-casting alloy worldwide due to its balanced properties and proven performance.

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 3320 gallon liquid totes Special package is available on request.