7072-O Aluminum alloy,Aluminum 7072-O alloy，E FORU

### **7072-O Aluminum Alloy: Annealed Cladding and Finstock Alloy** **7072 Aluminum Alloy** in the O temper (annealed) is a non-heat-treatable aluminum-zinc alloy in its softest and most ductile state. This condition provides maximum formability, making it ideal for complex forming operations and applications requiring extensive fabrication. --- #### **1. Chemical Composition** | Element | Content (%) (Typical) | Role in the Alloy | | :--- | :--- | :--- | | **Zinc (Zn)** | 0.8 - 1.3 | Provides galvanic protection and lowers electrochemical potential | | **Iron (Fe)** | 0.6 - 1.0 | Increases strength and improves finstock performance | | **Silicon (Si)** | ≤ 0.10 | Impurity element | | **Copper (Cu)** | ≤ 0.10 | Impurity element | | **Manganese (Mn)** | ≤ 0.10 | Impurity element | | **Magnesium (Mg)** | ≤ 0.10 | Impurity element | | **Chromium (Cr)** | ≤ 0.04 | Impurity element | | **Titanium (Ti)** | ≤ 0.05 | Impurity element | | **Other Elements** | ≤ 0.05 each; ≤ 0.15 total | - | | **Aluminum (Al)** | Balance | Base metal | --- #### **2. Understanding the O Temper** The O temper designation indicates: - Fully annealed condition - Softest state with maximum ductility - Lowest strength characteristics - Recrystallized microstructure **Key Characteristics:** - Maximum formability and ductility - Lowest strength and hardness - Homogeneous microstructure - Ideal for severe forming operations - Stress-relieved condition --- #### **3. Physical Properties** | Property | Value / Description | | :--- | :--- | | **Density** | 2.72 g/cm³ (0.098 lb/in³) | | **Melting Range** | 640°C - 655°C (1184°F - 1211°F) | | **Electrical Conductivity** | 50-54% IACS | | **Thermal Conductivity** | 190-210 W/m·K | | **Coefficient of Thermal Expansion** | 23.6 × 10⁻⁶/°C (20-100°C) | | **Modulus of Elasticity** | 69 GPa (10.0 × 10⁶ psi) | --- #### **4. Mechanical Properties (Typical)** | Property | Typical Value | | :--- | :--- | | **Tensile Ultimate Strength** | 95 - 125 MPa (14 - 18 ksi) | | **Tensile Yield Strength (0.2% Offset)** | 35 - 70 MPa (5 - 10 ksi) | | **Elongation** | 20-30% | | **Shear Strength** | 60 - 85 MPa (9 - 12 ksi) | | **Fatigue Strength** | 40 - 55 MPa (6 - 8 ksi) | | **Brinell Hardness** | 20 - 35 HB | --- #### **5. Product Applications** **7072-O** is primarily used in applications requiring maximum formability: * **Cladding Applications:** * Protective cladding for brazing sheets * Architectural panel cladding * Marine component cladding * Corrosion protection layers * **Heat Exchanger Components:** * Fins for air conditioning systems * Radiator fins * Heat exchanger tubes * HVAC system components * **Deep Drawing Applications:** * Complex shaped components * * Deep drawn parts * Severely formed products * **Electrical Applications:** * Heat sink components * Electrical conductor cladding * Electronic packaging * **Other Applications:** * Packaging materials * Decorative trim * Building products --- #### **6. International Standards** | Standard Body | Designation | Specification | | :--- | :--- | :--- | | **Aluminum Association** | 7072-O | AA Teal Sheets | | **ASTM International** | 7072-O | ASTM B209 / B479 | | **Aerospace (AMS)** | 7072 | AMS 4007 | | **European Norm** | EN AW-7072 O | EN 485-2 | | **Unified Numbering System** | A97072 | UNS Registry | --- #### **7. Key Characteristics** **Advantages:** - **Maximum formability and ductility** - **Excellent sacrificial corrosion protection** when clad to core alloys - High thermal conductivity - Good electrical conductivity - Excellent surface finish characteristics - Homogeneous microstructure - Suitable for most severe forming operations **Limitations:** - Lowest strength of all tempers - Not suitable for structural applications - Limited resistance to deformation - Requires careful handling to prevent damage --- #### **8. Manufacturing Considerations** * **Forming:** Excellent formability - suitable for deep drawing and severe forming * **Joining:** Excellent weldability and brazeability * **Machining:** Poor machinability due to softness and gummy nature * **Surface Treatment:** Excellent for anodizing and coating * **Heat Treatment:** Non-heat-treatable - can be strain-hardened after forming --- #### **9. Special Features** **7072-O** offers unique functional characteristics: * **Galvanic Protection:** Excellent sacrificial corrosion protection due to electrochemical potential * **Thermal Performance:** Superior heat transfer characteristics * **Manufacturing Versatility:** Can be roll-bonded to other aluminum alloys * **Surface Quality:** Provides excellent surface finish for decorative applications * **Formability:** Capable of withstanding the most severe forming operations without cracking The O temper is particularly valuable for applications requiring: - Complex deep drawing operations - Severe forming processes - Applications where the material will be strain-hardened during fabrication - Brazing applications where maximum formability is required **7072-O Aluminum Alloy** serves as the ideal starting material for manufacturing processes that require extensive forming, after which the material may be used in the as-formed condition or subsequently heat-treated if applicable to core materials in clad products.

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 2165 gallon liquid totes Special package is available on request.