Magnesium AM100A-T7, Cast,E FOUR

### **Product Datasheet: Magnesium AM100A-T7 Cast Alloy** **Introduction** Magnesium AM100A-T7 is a heat-treated magnesium casting alloy that undergoes solution heat treatment followed by stabilization annealing. The T7 temper is specifically designed to provide maximum dimensional stability and relief of residual stresses, while maintaining good mechanical properties and enhancing resistance to stress corrosion cracking. This treatment makes AM100A-T7 particularly suitable for applications requiring long-term dimensional accuracy under varying thermal conditions. **Key Characteristics** - **Excellent Dimensional Stability**: Ideal for precision components - **Enhanced Stress Corrosion Resistance**: Superior performance in corrosive environments - **Good Elevated Temperature Performance**: Maintains properties at elevated temperatures - **Reduced Residual Stresses**: Minimizes distortion in service - **Improved Microstructural Stability**: Withstands thermal cycling --- #### **1. Chemical Composition (Weight %)** The composition conforms to standard specifications for AM100A alloy: | Element | Content (%) | |---------|-------------| | **Aluminum (Al)** | 9.3 - 10.7 | | **Manganese (Mn)** | 0.10 - 0.30 | | **Zinc (Zn)** | ≤ 0.30 | | **Silicon (Si)** | ≤ 0.30 | | **Copper (Cu)** | ≤ 0.10 | | **Iron (Fe)** | ≤ 0.005 | | **Nickel (Ni)** | ≤ 0.01 | | **Other Elements** | ≤ 0.30 (each) | | **Total Impurities** | ≤ 0.50 | | **Magnesium (Mg)** | Remainder | --- #### **2. Physical Properties** | Property | Value | |----------|--------| | **Density** | 1.81 g/cm³ (0.065 lb/in³) | | **Melting Range** | 460 - 595°C (860 - 1105°F) | | **Thermal Conductivity** | 55-65 W/m·K | | **Coefficient of Thermal Expansion** | 25.8-26.2 µm/m·K (20-100°C) | | **Modulus of Elasticity** | 44-46 GPa (6.4-6.7 × 10⁶ psi) | | **Specific Heat Capacity** | 1050 J/kg·K | | **Electrical Resistivity** | 120-140 nΩ·m | --- #### **3. Mechanical Properties (T7 Condition)** **Room Temperature Properties:** | Property | Value | |----------|--------| | **Tensile Strength, Ultimate** | 170-200 MPa (24,600-29,000 psi) | | **Tensile Strength, Yield (0.2% Offset)** | 100-120 MPa (14,500-17,400 psi) | | **Elongation** | 3-6% (in 2 inches) | | **Compressive Yield Strength** | 100-120 MPa (14,500-17,400 psi) | | **Hardness, Brinell** | 60-70 HB | | **Shear Strength** | 120-140 MPa (17,400-20,300 psi) | | **Fatigue Strength** | 70-80 MPa (10,100-11,600 psi) | **Elevated Temperature Properties:** - Stable mechanical properties up to 150°C (300°F) - Excellent creep resistance at elevated temperatures - Good thermal fatigue resistance - Maintains dimensional stability under thermal cycling --- #### **4. International Standards** AM100A-T7 is recognized in several international standards: - **ASTM Standards:** - **ASTM B80**: Standard Specification for Magnesium-Alloy Sand Castings - **ASTM B199**: Standard Specification for Magnesium-Alloy Permanent Mold Castings - **ASTM B403**: Standard Specification for Magnesium-Alloy Investment Castings - **SAE**: **SAE J465** - Wrought and Cast Magnesium Alloys - **AMS**: **AMS 4439** (Covers heat-treated conditions) - **UNS**: **M10100** - **ISO**: **ISO 16220** - Magnesium and magnesium alloys - Magnesium alloy ingots and castings - **DIN**: **DIN 1729-2** - Magnesium casting alloys --- #### **5. Product Applications** AM100A-T7 is specified for applications requiring dimensional stability and stress corrosion resistance: **Aerospace Applications:** - Aircraft instrument housings - Guidance system components - Optical mounting platforms - Satellite components **Military Applications:** - Fire control system housings - Radar base plates - Weapon system components - Communication equipment enclosures **Industrial Applications:** - Precision measuring instrument frames - Machine tool components - Coordinate measuring machine parts - Semiconductor manufacturing equipment **Automotive Applications:** - Racing transmission cases - High-performance engine components - Specialty vehicle structural parts --- #### **6. Heat Treatment Specification** **T7 Heat Treatment Process:** - **Solution Treatment**: 425±5°C (797±9°F) for 8-16 hours - **Quenching**: Hot water quenching at 70-100°C (158-212°F) - **Stabilization**: 215±5°C (419±9°F) for 4-8 hours - **Cooling**: Controlled cooling to room temperature **Microstructural Features:** - Homogenized grain structure - Stable precipitate distribution - Reduced internal stresses - Coarsened intermetallic phases for stability --- #### **7. Manufacturing Considerations** **Casting Recommendations:** - Excellent for sand casting of complex shapes - Suitable for permanent mold casting - Recommended for investment casting of precision parts - Controlled solidification rate critical for optimal properties **Machinability:** - Good machining characteristics - Stable during precision machining operations - Minimal distortion during heavy machining - Recommended cutting tools: Sharp carbide tools **Joining Methods:** - TIG welding with post-weld stress relief - Adhesive bonding for maximum stability - Mechanical fastening preferred for critical applications - Special precautions for welding due to stress relief temper **Surface Protection:** - Chromate conversion coating for corrosion protection - Anodizing treatments (HAE process) - Electroless nickel plating - Painting and powder coating systems --- **Technical Notes:** 1. T7 treatment provides optimal stability for precision applications 2. Ideal for components subject to thermal cycling 3. Superior stress corrosion resistance compared to T6 temper 4. Recommended for large, complex castings requiring dimensional stability 5. Stress relief after machining may be required for critical applications **Disclaimer:** This information is provided for reference purposes only. Actual properties may vary depending on casting method, section size, and foundry practices. Users should verify suitability for specific applications through appropriate testing and consult current material specifications for design and procurement purposes. The T7 heat treatment parameters should be optimized for specific casting configurations and performance requirements.

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 3273 gallon liquid totes Special package is available on request.