2024-T851 Aluminum alloy,Aluminum 2024-T851 alloy,E FORU

## # **Aluminum 2024-T851 Alloy Product Introduction** **Overview** 2024-T851 is a high-strength aluminum-copper alloy that has undergone solution heat treatment, stress-relieving by stretching, and artificial aging to achieve superior mechanical properties and dimensional stability. This temper is specifically designed for plate and rolled ring products where controlled stretching (typically 1.5-3%) provides optimal stress relief for precision machining applications. --- #### **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 (Plate):** | Property | Value | |----------|-------| | **Tensile Strength** | 455-490 MPa (66-71 ksi) | | **Yield Strength (0.2% Offset)** | 330-365 MPa (48-53 ksi) | | **Elongation in 2 inches** | 5-9% | | **Shear Strength** | 280-300 MPa (41-44 ksi) | | **Fatigue Strength** | 145 MPa (21 ksi) | | **Brinell Hardness** | 130-140 HB | | **Compressive Yield Strength** | 330-365 MPa (48-53 ksi) | --- #### **4. International Standards** | Standard System | Designation | Product Form | |-----------------|-------------|--------------| | **ASTM** | ASTM B209 | Plate | | **AMS** | AMS 4081 | Plate | | **AMS** | AMS 4201 | Rolled Ring | | **MIL** | MIL-DTL-6075 | Plate | | **EN** | EN AW-2024A [T851] | Plate | --- #### **5. Product Applications** **Aerospace Primary Structures:** - Aircraft wing planks and spars - Fuselage bulkheads and frames - Landing gear support components - Helicopter rotor components - Space vehicle structural members **Defense Applications:** - Military aircraft structural components - Missile airframes and wings - Armored vehicle structural elements - Defense system mounting structures **Precision Applications:** - Machined structural components - Aircraft fittings and brackets - High-stress machined parts - Tooling and fixtures requiring stability --- #### **6. Key Advantages & Considerations** **Advantages:** - ✅ **Superior Dimensional Stability** for precision machining - ✅ **Enhanced Strength Properties** over T3/T4 tempers - ✅ **Improved Stress-Corrosion Resistance** - ✅ **Excellent Fatigue Performance** - ✅ **Minimal Machining Distortion** - ✅ **Consistent Mechanical Properties** **Considerations:** - ⚠️ **Reduced Ductility** compared to T3/T4 tempers - ⚠️ **Limited Formability** after final heat treatment - ⚠️ **Poor Weldability** - not recommended for fusion welding - ⚠️ **Requires Corrosion Protection** in service environments - ⚠️ **Higher Cost** due to additional processing steps --- **Heat Treatment Process** **T851 Temper Process:** 1. **Solution Heat Treatment:** - Temperature: 490-500°C (915-932°F) - Controlled atmosphere heating - Rapid quenching 2. **Stress Relieving:** - 1.5-3% permanent stretch - Controlled stretching process - Stress equalization 3. **Artificial Aging:** - Temperature: 180-195°C (355-383°F) - Time: 8-12 hours - Controlled cooling cycle --- **Machining Characteristics** **Machinability:** Excellent for high-strength aluminum **Tooling:** Carbide tools recommended **Dimensional Stability:** Superior for precision components **Surface Finish:** Excellent with proper techniques --- **Quality Assurance** **Testing Requirements:** - Mechanical property verification - Ultrasonic inspection - Stress-corrosion testing - Microstructure examination - Dimensional verification --- **Conclusion** 2024-T851 aluminum alloy represents a premium grade material specifically engineered for critical aerospace applications requiring high strength, excellent fatigue resistance, and superior dimensional stability. The controlled stretching process in the T851 temper provides exceptional stress relief, making it ideally suited for complex machined components where dimensional accuracy and stability are paramount. While demanding appropriate corrosion protection and specialized manufacturing techniques, its proven performance in aircraft primary structures and defense applications justifies its position as a material of choice for engineers designing highly stressed, precision components. The combination of enhanced mechanical properties and machining stability ensures reliable performance in the most demanding aerospace and defense applications.

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 1548 gallon liquid totes Special package is available on request.