7047 Aluminum alloy,Aluminum 7047 alloy，E FORU

### **7047 Aluminum Alloy: Product Introduction** **7047 Aluminum Alloy** is a high-strength, heat-treatable alloy from the 7xxx series (Al-Zn-Mg-Cu system). It is specifically formulated to provide an excellent combination of high strength and superior resistance to exfoliation corrosion and stress corrosion cracking (SCC). This makes it a versatile material, particularly well-suited for applications in the aerospace and defense industries, especially for thick sections where through-thickness properties are critical. --- #### **1. Chemical Composition** The balance of zinc, magnesium, and copper in 7047 is key to its unique properties. The following table outlines the typical weight percentage of its key elements. | Element | Content (%) (Typical) | Role in the Alloy | | :--- | :--- | :--- | | **Zinc (Zn)** | 6.8 - 7.8 | Primary strengthening element; forms the main hardening precipitates (MgZn₂). | | **Magnesium (Mg)** | 1.8 - 2.4 | Co-operates with Zn to form the strengthening η' phase during aging. | | **Copper (Cu)** | 0.50 - 1.0 | Enhances strength and critically improves resistance to stress corrosion cracking. | | **Chromium (Cr)** | 0.08 - 0.18 | Forms dispersoids that control grain structure and improve toughness and corrosion resistance. | | **Manganese (Mn)** | 0.05 - 0.25 | Works with Cr to control grain structure and improve strength. | | **Iron (Fe)** | ≤ 0.25 | Impurity (controlled to maintain toughness). | | **Silicon (Si)** | ≤ 0.20 | Impurity (controlled to maintain toughness). | | **Titanium (Ti)** | ≤ 0.06 | - | | **Other Impurities** | ≤ 0.05 each; ≤ 0.15 total | - | | **Aluminum (Al)** | Balance | Base metal. | **Key Difference from 7046/7046A:** 7047 typically has a **slightly lower Zinc content** and a **higher Chromium content**, which contributes to its improved corrosion resistance profile. --- #### **2. Physical Properties** The physical properties of 7047 alloy are typical for high-strength aluminum alloys. | Property | Value / Description | | :--- | :--- | | **Density** | ≈ 2.80 g/cm³ (0.101 lb/in³) | | **Melting Range** | ≈ 475°C - 635°C (887°F - 1175°F) | | **Electrical Conductivity** | ≈ 38-42% IACS (International Annealed Copper Standard) | | **Thermal Conductivity** | ≈ 115-135 W/m·K | | **Coefficient of Thermal Expansion** | ≈ 23.6 x 10⁻⁶/°C (20-100°C) | | **Modulus of Elasticity (E)** | ≈ 71 GPa (10.3 x 10⁶ psi) | --- #### **3. Mechanical Properties (Typical for T7651 Temper)** The T7651 temper (Solution Heat-Treated, Stress-Relieved by Stretching, and Artificially Aged to an **Over-Aged** condition) is commonly used for plate to achieve its optimal corrosion resistance. | Property | Typical Value | | :--- | :--- | | **Tensile Strength (Ultimate)** | 510 - 550 MPa (74 - 80 ksi) | | **Tensile Yield Strength (0.2% Offset)** | 440 - 480 MPa (64 - 70 ksi) | | **Elongation (in 50 mm / 2 in)** | 9 - 11 % | | **Hardness (Brinell)** | ≈ 140 HB | --- #### **4. Product Applications** 7047 Aluminum Alloy is used in applications demanding a balance of strength and corrosion resistance, particularly in thick sections. * **Aerospace & Defense Industry:** * **Airframe Components:** Fuselage frames, wing ribs, and bulkheads. * **Military Vehicle Armor Plate.** * **Helicopter Structural Parts.** * **Marine & Offshore Applications:** * Superstructures and masts for high-performance vessels. * Components exposed to a marine atmosphere. * **Other High-Strength Applications:** * Large, thick machining pre-forms for the tooling industry. * Critical components in heavy-duty machinery. --- #### **5. International Standards** 7047 alloy is recognized and specified by several major international standards organizations. | Standard Body | Alloy Designation | Common Forms | Relevant Standard | | :--- | :--- | :--- | :--- | | **Aluminum Association (AA)** | **7047** | Plate, Forging Stock | AA Teal Sheets / ANSI H35.1 | | **ASTM International** | **Aluminum 7047** | Plate | ASTM B209 (Standard Specification for Aluminum and Aluminum-Alloy Sheet and Plate) | | **Aerospace (AMS)** | **7047** | Plate | AMS 4116 (Plate) | | **European Norm (EN)** | **EN AW-7047** | Wrought Products | EN 485-2 (Sheet/Plate), EN 755-2 (Extruded Products) | | **Unified Numbering System (UNS)** | **A97047** | - | SAE J1086 | --- #### **Key Advantages & Summary** * **Excellent Combination of Strength & Corrosion Resistance:** Offers a more favorable balance than many other high-strength 7xxx alloys like 7075. * **Superior Exfoliation Corrosion Resistance:** Particularly resistant to the layered form of corrosion common in rolled or forged products. * **Good Stress Corrosion Cracking (SCC) Resistance:** The over-aged tempers (e.g., T76, T7651) are specifically designed to maximize SCC resistance, making it suitable for use under sustained tensile stress. * **Good Machinability:** Can be machined effectively in the T76-type temper. * **Good Forgability:** Often used as a forging stock for complex, high-strength parts. In conclusion, **7047 Aluminum Alloy** is a highly engineered material that prioritizes a balance of properties. While its ultimate strength may be slightly lower than some peak-aged 7xxx alloys, its superior corrosion resistance, especially in exfoliation and stress corrosion, makes it an indispensable choice for aerospace, marine, and military applications where long-term durability and structural integrity in harsh environments 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 2142 gallon liquid totes Special package is available on request.