7049-T352 Aluminum alloy,Aluminum 7049-T352 alloy，E FORU

### **7049-T352 Aluminum Alloy: High-Strength Forging Stock** **7049-T352 Aluminum Alloy** is a specific temper of the high-strength 7049 Al-Zn-Mg-Cu alloy. This designation refers to the alloy supplied as a **forging stock** (such as a die forging blank or hand forging stock) that has been solution heat-treated and stress-relieved by **compression**. This specific thermal-mechanical processing makes it ideally suited for further forging operations, followed by final heat treatment to achieve its world-class mechanical properties. It is renowned for its exceptional strength and good stress corrosion cracking resistance after full aging. --- #### **1. Chemical Composition** The composition of the base 7049 alloy is designed for ultra-high strength. The T352 temper does not alter the chemistry. | Element | Content (%) (Typical) | Role in the Alloy | | :--- | :--- | :--- | | **Zinc (Zn)** | 7.2 - 8.4 | Primary strengthening element; forms the main hardening precipitates (MgZn₂). | | **Magnesium (Mg)** | 2.0 - 2.9 | Co-operates with Zn to form the strengthening η' phase during aging. | | **Copper (Cu)** | 1.2 - 1.9 | Critically enhances strength and improves resistance to stress corrosion cracking. | | **Chromium (Cr)** | 0.10 - 0.22 | Forms dispersoids that control grain structure and improve toughness. | | **Iron (Fe)** | ≤ 0.15 | Impurity (controlled to maintain toughness). | | **Silicon (Si)** | ≤ 0.12 | Impurity (controlled to maintain toughness). | | **Manganese (Mn)** | ≤ 0.20 | - | | **Titanium (Ti)** | ≤ 0.10 | - | | **Other Impurities** | ≤ 0.05 each; ≤ 0.15 total | - | | **Aluminum (Al)** | Balance | Base metal. | --- #### **2. Understanding the T352 Temper** The temper designation is key to understanding this product form: * **T3**: Solution Heat-Treated and then Cold Worked. * **52**: Specifically indicates that the product has been stress-relieved by **compression** to produce a permanent set of 1% to 5% (e.g., by cold compression forging or rolling). **Key Characteristics of T352 Condition:** * It is in a **soft, relatively ductile state**. * It has not been artificially aged to its final high strength. * The compression stress-relieving provides dimensional stability and a refined microstructure. * This condition is ideal for subsequent **forging or machining operations**. * After the final shaping, the component must be **solution heat-treated, quenched, and artificially aged** (typically to a T73 or T76 temper) to develop its full strength and corrosion resistance. --- #### **3. Physical Properties** Physical properties are for the base 7049 alloy. | Property | Value / Description | | :--- | :--- | | **Density** | ≈ 2.84 g/cm³ (0.102 lb/in³) | | **Melting Range** | ≈ 475°C - 635°C (887°F - 1175°F) | | **Electrical Conductivity** | ≈ 35-40% IACS (International Annealed Copper Standard) | | **Thermal Conductivity** | ≈ 105-125 W/m·K | | **Coefficient of Thermal Expansion** | ≈ 23.2 x 10⁻⁶/°C (20-100°C) | | **Modulus of Elasticity (E)** | ≈ 71 GPa (10.3 x 10⁶ psi) | --- #### **4. Mechanical Properties (As T352 & After Final Aging)** | Property | T352 Condition (Typical) | After Final Aging to T73 (Typical) | | :--- | :--- | :--- | | **Tensile Strength (Ultimate)** | ~ 345 MPa (50 ksi) | 530 - 570 MPa (77 - 83 ksi) | | **Tensile Yield Strength (0.2% Offset)** | ~ 255 MPa (37 ksi) | 460 - 500 MPa (67 - 73 ksi) | | **Elongation** | ~ 12% | 8 - 11 % | | **Hardness (Brinell)** | ~ 90 HB | ~ 150 HB | --- #### **5. Product Applications** 7049-T352 is exclusively used as a **forging stock** for manufacturing critical, high-strength components. * **Aerospace Industry (Primary Application):** * **Pre-forms for Aircraft Landing Gear:** Main fittings, beams, and pistons. * **Airframe Forgings:** Wing spar attachments, fuselage frames, and bulkheads. * **Rocket and Missile Components.** * **Defense Industry:** * **Armored Vehicle Components:** Track shoes, hatches, and structural supports. --- #### **6. International Standards** 7049-T352 is specified in major aerospace standards, particularly those governing forging stock. | Standard Body | Alloy Designation | Common Forms | Relevant Standard | | :--- | :--- | :--- | :--- | | **Aluminum Association (AA)** | **7049-T352** | Forging Stock | AA Teal Sheets / ANSI H35.1 | | **Aerospace (AMS)** | **7049** | Die Forging Stock | **AMS 4123** (This standard specifically covers 7049 Alloy, Die Forgings, T352 Temper) | | **ASTM International** | **Aluminum 7049** | - | ASTM B247 (Specification for Aluminum and Aluminum-Alloy Die Forgings, Hand Forgings, and Rolled Ring Forgings) | --- #### **Key Advantages & Summary** * **Optimal Forgeability:** The T352 condition provides a soft, stable, and uniform microstructure that is ideal for complex forging operations without cracking. * **Dimensional Stability:** The compression stress-relieving minimizes distortion during subsequent machining or final heat treatment. * **Path to Ultra-High Strength:** Serves as the intermediary product to create components with the renowned strength of fully-aged 7049 (e.g., T73 temper). * **Superior Final Properties:** After final heat treatment, components made from 7049-T352 stock achieve an excellent balance of very high strength and good stress corrosion cracking resistance. In conclusion, **7049-T352 Aluminum Alloy** is not a finished component but a specialized **semi-finished product**. It is the essential starting material for forgers to manufacture the most demanding aerospace and defense components, which, after final processing, will exhibit the world-class performance the 7049 alloy is famous for.

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 2144 gallon liquid totes Special package is available on request.