Magnesium AM100A-T61, Sand Cast，ASTM B 403 (Ingot UNS M10101),E FOUR

### **Product Datasheet: Magnesium AM100A-T61 Sand Casting Alloy (UNS M10101)** **Introduction** Magnesium AM100A-T61 is a high-strength sand casting alloy primarily known for its excellent combination of strength, ductility, and impact resistance. The "A" indicates aluminum is the principal alloying element, "M" stands for manganese, and "100" denotes approximately 10% aluminum. The **-T61** temper is critical: it signifies that the casting has been solution heat-treated and then artificially aged. This specific thermal processing significantly enhances the alloy's yield strength and hardness compared to the as-cast condition. It is commonly produced via sand casting, which allows for the creation of large, complex, and low-volume components. **Key Features** * **High Strength and Ductility:** Offers an excellent balance of tensile strength and elongation. * **Excellent Impact Resistance:** Superior to many other magnesium casting alloys, making it suitable for structural components. * **Good Damping Capacity:** Inherits magnesium's inherent ability to absorb vibration and shock. * **Good Corrosion Resistance:** Provides respectable resistance to atmospheric corrosion, particularly when properly surface-treated. --- #### **1. Chemical Composition (Weight %)** The composition of AM100A per ASTM B403 (Ingot) is as follows: | 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 Impurities** | ≤ 0.30 (total) | | **Magnesium (Mg)** | Remainder | --- #### **2. Physical Properties** | Property | Value | | :---------------------------- | :-------------------------------------------- | | **Density** | 1.81 g/cm³ (0.065 lb/in³) | | **Melting Point** | ~ 460 - 595°C (860 - 1105°F) | | **Thermal Conductivity** | ~ 55 W/m·K | | **Coefficient of Thermal Expansion** | ~ 26.0 µm/m·K at 20-100°C | | **Modulus of Elasticity** | 45 GPa (6.5 x 10⁶ psi) | --- #### **3. Mechanical Properties (Typical for Sand Cast T61 Temper)** The T61 heat treatment (Solution Heat Treated and Artificially Aged) is designed to maximize yield strength and hardness. **Room Temperature Properties (Typical Minimums/Averages):** | Property | Value | | :----------------------------- | :-------------------------------------------- | | **Tensile Strength, Ultimate** | 240 MPa (35,000 psi) | | **Tensile Strength, Yield (0.2% Offset)** | 130 MPa (19,000 psi) | | **Elongation** | 6% (in 2 inches) | | **Compressive Yield Strength** | 130 MPa (19,000 psi) | | **Hardness, Brinell** | 60 - 65 HB | --- #### **4. International Standards** AM100A is covered by several key international standards for castings and ingots. * **ASTM:** * **ASTM B403** - Standard Specification for Magnesium-Alloy Investment Castings (Covers ingot specification for AM100A). * **ASTM B80** - Standard Specification for Magnesium-Alloy Sand Castings (Directly covers sand cast components). * **ASTM B199** - Standard Specification for Magnesium-Alloy Permanent Mold Castings. * **AMS:** **AMS 4439** - Castings, Magnesium Alloy, Sand 9.5Al-0.13Mn (AM100A) Solution and Precipitation Heat Treated. * **SAE:** **SAE J465** - Wrought and Cast Magnesium Alloys. * **UNS:** **M10101** * **Federal Standard:** **QQ-M-56** (Historical) --- #### **5. Product Applications** The combination of strength, ductility, and impact resistance makes AM100A-T61 suitable for demanding structural and aerospace applications. * **Aerospace & Defense:** * **Aircraft Wheels and Brakes:** A traditional and major application where high strength and good heat dissipation are critical. * **Gearbox Housings and Transmission Cases:** For helicopters and fixed-wing aircraft. * **Engine Accessory Housings:** Requires strength to withstand operational vibrations. * **Missile and Avionics Housings:** Where light weight and structural integrity are paramount. * **High-Performance Automotive:** * **Racing Wheel Hubs and Components.** * **Industrial:** * **Parts for Textile Machinery.** * **Jigs and Fixtures** in manufacturing. **Casting & Heat Treatment Notes:** * **Process:** Primarily used for **Sand Casting** and Permanent Mold Casting, which allows for large and complex geometries. * **The T61 Temper Process:** 1. **Solution Heat Treatment:** The casting is heated to a high temperature (typically ~425°C / 800°F) and held to dissolve alloying elements into the magnesium matrix, then rapidly quenched. 2. **Artificial Aging:** The part is then heated to a lower temperature (typically ~215°C / 420°F) for a prolonged period to precipitate strengthening phases uniformly throughout the structure. * **Machining:** Exhibits excellent machinability, allowing for high cutting speeds and good surface finishes. * **Corrosion Protection:** Cast components require standard surface finishing for corrosion protection, such as chromate conversion coating (e.g., Dow No. 7), anodizing, or painting. --- **Disclaimer:** This information is for reference purposes only. Properties can vary based on foundry practice, section thickness, and specific heat treatment parameters. It is essential to consult the latest official material specifications (e.g., ASTM B80 for sand castings) for design, procurement, and manufacturing. The suitability of the material for any specific application must be evaluated by the user.

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 3269 gallon liquid totes Special package is available on request.