Magnesium AZ31B-O (UNS M11311)
Magnesium AZ31B-O is a non-heat-treatable magnesium alloy valued for its exceptional strength-to-weight ratio, corrosion resistance, and ease of fabrication. Commonly used in aerospace, transportation, and consumer products, it provides an optimal balance of performance and lightweight characteristics, especially where weight reduction is key.
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| Chemical Composition | ||
|---|---|---|
| Element | Min | Max |
| Magnesium | —— | Remainder |
| Aluminum | 2.5% | 3.5% |
| Calcium | —— | 0.04% |
| Copper | —— | 0.05% |
| Iron | —— | 0.005% |
| Manganese | 0.2% | —— |
| Nickel | —— | 0.005% |
| Silicon | —— | 0.1% |
| Zinc | 0.6% | 1.4% |
The following table provides a list of magnesium AZ31B-O properties in both SI and US customary/Imperial units.
Click on the button to switch between Metric and Imperial units.
| Physical Properties | Metric |
|---|---|
| Density | 1770 kg/m3 |
| Mechanical Properties | Metric |
| Tensile Strength (Ultimate) | 255 MPa |
| Tensile Strength (Yield) | 150 MPa |
| Compressive Strength (Yield) | 110 MPa |
| Bearing Strength (Ultimate) | 485 MPa |
| Bearing Strength (Yield) | 290 MPa |
| Fatigue Strength # of Cycles 1.0e+7 | 120 - 145 MPa |
| Shear Strength | 145 MPa |
| Young’s Modulus (E) | 45 GPa |
| Shear Modulus (G) | 17 GPa |
| Elongation at Break in 50 mm | 21% |
| Poisson’s Ratio (ν) | 0.35 |
| Brinell Hardness 500 kg load, 10 mm ball | 56 |
| Knoop Hardness Converted from Brinell | 71 |
| Vickers Hardness Converted from Brinell | 83 |
| Machinability | 100% |
| Thermal Properties | Metric |
| Melting Point | 605 - 630 °C |
| Solidus | 605 °C |
| Liquidus | 630 °C |
| Thermal Conductivity | 96 W/m·K |
| Specific Heat Capacity (Cp) | 1000 J/kg·K |
| Coefficient of Thermal Expansion (αL) | 26.0 1/°C |
| Heat of Fusion | 340 J/g |
| Electrical Properties | Metric |
| Electrical Resistivity | 9.20×10-6 Ω·cm |
The values in this table are approximate and can vary depending on various factors such as the specific manufacturing process and heat treatment applied to the alloy.
Advantages & Disadvantages of Magnesium AZ31B-O
| Advantages | Disadvantages |
|---|---|
| Low density | Limited availability |
| Excellent corrosion resistance | Requires specialized welding techniques |
| Good machinability and formability | Limited temperature range for structural applications |
| Recyclable and environmentally friendly | |
| Good damping capacity |
Applications of Magnesium AZ31B-O
Magnesium AZ31B-O is widely used in industries requiring lightweight and durable materials, including:
- Automotive Industry: Widely used for lightweight structural parts such as body panels, interior trim, seat frames, and brackets.
- Aerospace Industry: Applied in aircraft structures including fuselage components, wing panels, and interior parts.
- Electronics and Consumer Goods: Employed for lightweight, compact devices like laptop casings, cell phone frames, and camera housings.
- Sports and Recreation Equipment: Utilized in bicycle frames, golf club heads, tennis racket frames, and other lightweight sports equipment.
- Medical Applications: Used for lightweight orthopedic implants, surgical instruments, and medical devices.
- Industrial and General Applications: Employed in sheet metal forming, extrusions, die casting, and architectural applications like decorative panels.