2024-T81 Aluminum alloy,Aluminum 2024-T81 alloy,E FORU

### **Aluminum 2024-T81 Alloy Product Introduction** **Overview** 2024-T81 is a high-strength aluminum-copper alloy that has undergone solution heat treatment, cold working, and artificial aging to achieve an optimal balance of strength and stress-corrosion resistance. The T81 temper provides enhanced mechanical properties through controlled cold working (typically 1-3% stretch) followed by artificial aging, making it suitable for applications requiring both high strength and improved environmental durability. --- #### **1. Chemical Composition** | Element | Content (%) | |---------|-------------| | **Aluminum (Al)** | Balance | | **Copper (Cu)** | 3.8 - 4.9 | | **Magnesium (Mg)** | 1.2 - 1.8 | | **Manganese (Mn)** | 0.30 - 0.9 | | **Iron (Fe)** | ≤ 0.20 | | **Silicon (Si)** | ≤ 0.15 | | **Zinc (Zn)** | ≤ 0.10 | | **Chromium (Cr)** | ≤ 0.10 | | **Other Elements** | ≤ 0.15 total | --- #### **2. Physical Properties** | Property | Value / Description | |----------|---------------------| | **Density** | 2.78 g/cm³ (0.100 lb/in³) | | **Melting Range** | 500°C - 638°C (932°F - 1180°F) | | **Electrical Conductivity** | 30-35% IACS | | **Thermal Conductivity** | 121 W/m·K | | **Coefficient of Thermal Expansion** | 23.2 × 10⁻⁶/°C (20-100°C) | | **Modulus of Elasticity** | 73.1 GPa (10,600 ksi) | | **Poisson's Ratio** | 0.33 | --- #### **3. Mechanical Properties** **Typical Mechanical Properties:** | Property | Value | |----------|-------| | **Tensile Strength** | 450-485 MPa (65-70 ksi) | | **Yield Strength (0.2% Offset)** | 325-360 MPa (47-52 ksi) | | **Elongation in 2 inches** | 6-10% | | **Shear Strength** | 275-295 MPa (40-43 ksi) | | **Fatigue Strength** | 138 MPa (20 ksi) | | **Brinell Hardness** | 125-135 HB | | **Compressive Yield Strength** | 325-360 MPa (47-52 ksi) | --- #### **4. International Standards** | Standard System | Designation | Product Form | |-----------------|-------------|--------------| | **ASTM** | ASTM B209 | Sheet & Plate | | **AMS** | AMS 4037 | Sheet | | **AMS** | AMS 4081 | Plate | | **MIL** | MIL-DTL-6075 | Sheet | | **EN** | EN AW-2024A [T81] | Sheet/Plate | --- #### **5. Product Applications** **Aerospace Applications:** - Aircraft structural components - Wing skins and spars - Fuselage frames and stringers - Aircraft bulkheads - Aerospace fasteners and fittings **Defense Applications:** - Military aircraft structures - Missile components - Armored vehicle parts - Military equipment components **Industrial Applications:** - High-stress structural components - Machinery parts - Transportation equipment - Specialized tooling --- #### **6. Key Advantages & Considerations** **Advantages:** - ✅ **Enhanced Strength Properties** compared to T4 temper - ✅ **Improved Stress-Corrosion Resistance** vs T6 temper - ✅ **Good Fatigue Performance** - ✅ **Dimensional Stability** from cold working - ✅ **Excellent Strength-to-Weight Ratio** - ✅ **Good Machinability** **Considerations:** - ⚠️ **Reduced Ductility** compared to T3/T4 tempers - ⚠️ **Limited Formability** after final heat treatment - ⚠️ **Poor Weldability** - not recommended for fusion welding - ⚠️ **Requires Corrosion Protection** - ⚠️ **Higher Cost** than naturally aged tempers --- **Heat Treatment Process** **T81 Temper Process:** 1. **Solution Heat Treatment:** - Temperature: 490-500°C (915-932°F) - Soak time: Thickness dependent - Rapid quenching 2. **Cold Working:** - 1-3% permanent stretch - Stress relief operation 3. **Artificial Aging:** - Temperature: 180-195°C (355-383°F) - Time: 8-12 hours - Controlled cooling --- **Performance Characteristics** **Stress-Corrosion Resistance:** - Improved over T6 temper - Suitable for moderate stress environments - Good performance in industrial atmospheres **Fatigue Properties:** - Excellent fatigue strength - Good crack propagation resistance - Suitable for cyclic loading applications --- **Machining and Fabrication** **Machinability Rating:** Good **Tooling:** Standard high-speed steel or carbide tools **Coolant:** Recommended for optimal tool life **Surface Finish:** Good with proper machining parameters --- **Corrosion Protection** **Recommended Methods:** - Anodizing - Chemical conversion coatings - Paint systems - Regular maintenance --- **Conclusion** 2024-T81 aluminum alloy represents an optimized thermal-mechanical treatment that provides an excellent balance of high strength and improved stress-corrosion resistance. The combination of cold working and artificial aging in the T81 temper produces mechanical properties that are essential for critical aerospace and defense applications where both strength and environmental durability are important. While requiring appropriate corrosion protection and careful manufacturing consideration, its proven performance in demanding applications makes it a valuable material choice for engineers designing components that must withstand both mechanical stresses and corrosive environments. The T81 temper continues to be specified for applications where the enhanced properties justify the additional processing cost.

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 1547 gallon liquid totes Special package is available on request.