6061-T91 Aluminum alloy,Aluminum 6061-T91 alloy,E FORU

### **6061-T91 Aluminum Alloy: Product Introduction** **Overview** 6061-T91 aluminum alloy is a specialized temper of the 6061 aluminum-magnesium-silicon alloy system, representing an **advanced heat treatment condition** that provides a unique combination of properties. The T91 temper indicates material that has been **solution heat-treated, quenched, artificially aged, and then lightly cold worked** to achieve specific mechanical characteristics. This temper is designed to offer **enhanced strength and stability** for specialized applications requiring precise performance characteristics. --- #### **1. Chemical Composition (Weight %)** | Element | Minimum (%) | Maximum (%) | |---------|-------------|-------------| | Silicon (Si) | 0.40 | 0.8 | | Iron (Fe) | - | 0.7 | | Copper (Cu) | 0.15 | 0.40 | | Manganese (Mn) | - | 0.15 | | Magnesium (Mg) | 0.8 | 1.2 | | Chromium (Cr) | 0.04 | 0.35 | | Zinc (Zn) | - | 0.25 | | Titanium (Ti) | - | 0.15 | | Other (Each) | - | 0.05 | | Other (Total) | - | 0.15 | | **Aluminum (Al)** | **Balance** | | --- #### **2. Physical Properties** | Property | Typical Metric Value | Imperial Value | |----------|---------------------|----------------| | **Density** | 2.70 g/cm³ | 0.0975 lb/in³ | | **Melting Range** | 580 - 650 °C | 1075 - 1200 °F | | **Electrical Conductivity** | 42-46% IACS | 42-46% IACS | | **Thermal Conductivity** | 160-170 W/m·K | 930-985 BTU·in/(hr·ft²·°F) | | **Coefficient of Thermal Expansion** | 23.6 × 10⁻⁶/°C | 13.1 × 10⁻⁶/°F | --- #### **3. Mechanical Properties** **Typical Mechanical Properties for 6061-T91:** | Property | Typical Value (Metric) | Typical Value (Imperial) | |----------|------------------------|--------------------------| | **Tensile Strength** | 325-345 MPa | 47-50 ksi | | **Yield Strength (0.2% Offset)** | 295-315 MPa | 43-46 ksi | | **Elongation (in 50mm)** | 5-8% | 5-8% | | **Hardness (Brinell)** | 102-108 HB | 102-108 HB | | **Shear Strength** | 220-235 MPa | 32-34 ksi | | **Fatigue Strength** | 105-110 MPa | 15-16 ksi | **Key Characteristics of T91 Temper:** - Enhanced yield strength compared to T6 temper - Improved stress corrosion resistance - Good dimensional stability - Controlled cold working after aging provides additional strength - Balanced combination of strength and ductility --- #### **4. International Standards** * **ASTM (USA):** * ASTM B209: Standard Specification for Aluminum and Aluminum-Alloy Sheet and Plate * ASTM B211: Standard Specification for Aluminum and Aluminum-Alloy Bar, Rod, and Wire * ASTM B221: Standard Specification for Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes * **AMS (Aerospace Material Specification):** * AMS 4119: 6061-T91 Sheet and Plate * AMS 4339: 6061-T91 Extruded Shapes * **ISO (International Organization for Standardization):** * ISO 6361-2: Wrought aluminum and aluminum alloy sheets, strips and plates * ISO 6362-2: Wrought aluminum and aluminum alloy extruded rods/bars, tubes and profiles --- #### **5. Product Applications** **Aerospace & Defense:** - Aircraft structural components - Missile and rocket components - Satellite structures - Military vehicle components **Transportation Industry:** - High-performance automotive parts - Racing components - Specialized transportation equipment - Advanced mobility solutions **Industrial Applications:** - High-stress mechanical components - Precision machinery parts - Specialized tooling applications - Advanced manufacturing equipment **Sporting Goods:** - High-performance bicycle components - Professional sports equipment - Mountaineering and climbing gear - Competition-grade sporting goods --- #### **6. Key Characteristics & Advantages** * **Enhanced Mechanical Properties:** Superior strength characteristics compared to conventional tempers * **Improved Stability:** Excellent dimensional stability under load * **Good Stress Corrosion Resistance:** Enhanced performance in demanding environments * **Precision Performance:** Consistent and predictable mechanical behavior * **Maintained Weldability:** Suitable for joining with appropriate procedures * **Good Machinability:** Can be precision machined to close tolerances * **Thermal Stability:** Maintains properties at elevated temperatures --- #### **7. Heat Treatment and Processing** * **Solution Heat Treatment:** 530°C ± 10°C (985°F ± 15°F) * **Quenching:** Controlled quenching process * **Artificial Aging:** Specialized aging cycle at 160-180°C (320-355°F) * **Cold Working:** Light cold working (1-3% strain) after aging * **Quality Assurance:** Strict process control and testing requirements **Technical Note:** The T91 temper represents an advanced heat treatment sequence where the material undergoes artificial aging followed by a controlled cold working process. This sequence creates a unique microstructure that provides enhanced strength properties while maintaining adequate ductility. The temper is particularly valuable for applications requiring precise mechanical properties and enhanced performance characteristics beyond standard T6 capabilities. Special attention to process control is essential to achieve the desired property combination consistently.

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 1997 gallon liquid totes Special package is available on request.