Magnesium
Magnesium Alloys – The Lightest Structural Metal for Aerospace and Automotive Weight Reduction
Magnesium is the lightest structural metal available, with a density of only 1.74 g/cm³ — approximately 35% lighter than aluminum and 78% lighter than steel. AZ31 and AZ91 are the most common alloys, offering a practical combination of castability, machinability, and specific strength for aerospace brackets, automotive housings, and portable electronics where minimum mass is paramount.
Key Properties
- Density: 1.74 g/cm³ — lightest structural metal
- Tensile Strength: 260 MPa
- Yield Strength: 200 MPa
- Thermal Conductivity: 96 W/m·K
- Fire Safety: Fine chips are flammable — proper chip management and fire suppression required
- Standards: ASTM B90 / AMS 4377
Common Applications
Aerospace brackets and structural housings, automotive gearbox and transmission cases, portable electronics (laptops, cameras), bicycle components, and medical equipment where minimum weight is the overriding design requirement.
Material properties
| Material name | Magnesium |
|---|---|
| Type | Other Metals |
| Standard code | ASTM B90 / AMS 4377 |
| Tensile strength (MPa) | 260 |
| Yield strength (MPa) | 200 |
| Fatigue strength (MPa) | 97 |
| Elongation (%) | 15 |
| Hardness (Brinell) | 63 |
| Density (g/cm³) | 1.74 |
| Electrical resistivity (µΩ·in) | 9.2 |
| Thermal conductivity (W/m·K) | 96 |
| Melting range (°C) | 470–650 |
| Weldability | Fair |
| Formability | Good |
| Shear modulus | 17 |
| Industry code | magnesium |