Magnesium AZ31B-H26，UNS M11311;,E FOUR

Magnesium AZ31B-H26 (UNS M11311) Wrought Alloy Product Introduction** **Product Description:** Magnesium AZ31B-H26 is a strain-hardened temper variation of the widely used AZ31B wrought magnesium alloy. Designated under the Unified Numbering System as **UNS M11311**, the **-H26** temper indicates the material has been strain-hardened to a strength level between the partially annealed H24 and fully hard H28 conditions, then stabilized to ensure dimensional consistency. This specific temper offers higher strength than the more common H24 temper while maintaining adequate formability for many applications, making it suitable for components requiring enhanced mechanical performance. --- #### **1. Chemical Composition (Weight %)** The chemical composition maintains the strict impurity controls characteristic of the AZ31B specification. | Element | Minimum (%) | Maximum (%) | Key Function | | :--- | :--- | :--- | :--- | | **Aluminum (Al)** | 2.5 | 3.5 | Primary solid solution strengthener | | **Zinc (Zn)** | 0.6 | 1.4 | Enhances strength and corrosion resistance | | **Manganese (Mn)** | 0.2 | 1.0 | Improves corrosion resistance by forming stable compounds | | **Silicon (Si)** | - | 0.10 | Impurity control | | **Copper (Cu)** | - | 0.05 | Impurity control | | **Iron (Fe)** | - | 0.005 | Impurity control (strictly limited) | | **Nickel (Ni)** | - | 0.005 | Impurity control (strictly limited) | | **Other Elements** | - | 0.30 (total) | - | | **Magnesium (Mg)** | **Balance** | | | *Note: The precise chemical control, particularly the low limits on Fe, Cu, and Ni, ensures optimal corrosion performance for the H26 temper.* --- #### **2. Physical Properties** Physical properties remain consistent with the base AZ31B alloy, unaffected by the H26 temper. | Property | Value / Description | Condition | | :--- | :--- | :--- | | **Density** | 1.77 g/cm³ (0.064 lb/in³) | At 20°C | | **Melting Point** | ~ 605 - 630 °C (1121 - 1166 °F) | - | | **Thermal Conductivity** | 76 - 96 W/m·K | At 25°C | | **Coefficient of Thermal Expansion** | 26.0 μm/m·°C | 20 - 100°C | | **Electrical Resistivity** | ~ 92 nΩ·m | At 20°C | | **Modulus of Elasticity** | 45 GPa (6.5 x 10⁶ psi) | - | | **Shear Modulus** | 17 GPa (2.4 x 10⁶ psi) | - | | **Poisson's Ratio** | 0.35 | - | --- #### **3. Mechanical Properties (Typical for H26 Temper)** The H26 temper provides enhanced strength characteristics compared to H24, with a corresponding reduction in elongation. | Property | Typical Value (Sheet) | | :--- | :--- | | **Tensile Strength** | 270 - 290 MPa (39 - 42 ksi) | | **Yield Strength (0.2% Offset)** | 180 - 200 MPa (26 - 29 ksi) | | **Elongation** | 6 - 10% | | **Hardness** | 60 - 70 HB | *Note: The H26 temper offers approximately 10-15% higher yield strength than H24, making it suitable for applications requiring greater stiffness and load-bearing capacity.* --- #### **4. International Standards** AZ31B-H26 is covered under major international standards for wrought magnesium products. | Standard Organization | Standard Designation | | :--- | :--- | | **ASTM International** | **ASTM B90** (Sheet and Plate - includes H26 temper) | | **SAE International** | **SAE J465** | | **UNS (Unified Numbering System)** | **M11311** | | **ISO (International Org. for Standardization)** | **ISO 3116** (Wrought Magnesium and Magnesium Alloys) | --- #### **5. Product Applications** AZ31B-H26 is selected for applications requiring higher strength than H24 can provide, while still allowing for limited forming operations. * **Aerospace:** * Structural panels and stiffeners * Wing and fuselage components requiring higher stiffness * Mounting brackets and supports * Flooring components for high-traffic areas * **Automotive:** * Structural reinforcement panels * Bracket components for powertrain systems * Seat frame structural elements * Door impact beams * **Industrial:** * High-strength covers and enclosures * Material handling components * Platform and decking sections * Protective shielding requiring impact resistance --- #### **6. Key Characteristics & Considerations** * **Advantages:** * **Enhanced Strength:** Higher yield and tensile strength compared to H24 temper * **Good Stiffness:** Improved load-bearing capability while maintaining lightweight advantages * **Moderate Formability:** Can undergo light bending and forming operations * **Dimensional Stability:** The stabilization process ensures consistent performance * **Excellent Strength-to-Weight Ratio:** Maintains the fundamental advantage of magnesium alloys * **Considerations:** * **Reduced Ductility:** Lower elongation compared to H24 and O tempers limits severe forming operations * **Forming Limitations:** More susceptible to cracking during aggressive forming; may require intermediate annealing * **Corrosion Protection:** Like all magnesium alloys, requires appropriate coatings for corrosive environments * **Temperature Sensitivity:** Mechanical properties degrade above 120°C (250°F) **Summary:** **Magnesium AZ31B-H26 (UNS M11311)** represents an intermediate-to-high strength variant in the AZ31B temper range, offering a valuable balance between enhanced mechanical properties and practical manufacturability. It serves as an optimal choice for applications where the strength of H24 is insufficient but the formability limitations of the harder H28 temper are prohibitive, making it particularly valuable in aerospace and automotive structural applications where weight reduction and performance are critical.

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 3296 gallon liquid totes Special package is available on request.