Features of Magnesium

The Lightest Metallic Material

The density of the magnesium is about 2/3 of that of aluminum and a quarter of that of steel. Magnesium is the lightest among metallic materials which are being used practically.


Application: Automobile parts and portable electronic appliance parts

 

Strength and Toughness

Although magnesium alloy has a higher density than plastics, its tensile strength and Young's modulus per unit weight are higher than plastics.This enables to make a lighter part by using magnesium alloy than plastics.
 

Application: The frame and backside casing of liquid crystal panel for notebook PCs and mobile phones

 

Heat Dissipation

The thermal conductivity of magnesium alloy is much higher than that of plastics. Magnesium casings of electronic appliances can dissipate heat,which is generated in the electronic circuit, much more effectively than plastic casings.


Application: Casings for PCs, LCD projectors, and TV

 

EMI Shielding

Magnesium casing has a higher EMI shielding ability than plastic one with metallic plating.


Application: Mobile phone casings

 

Machinability

Magnesium alloy has a lower resistance against cutting than almost all other metallic materials, which enables rapid machining.

Resistance of metallic materials against cutting

(Relative value compared to magnesium alloy)

NAME

RESISTANCE

Magnesium alloy

1.0

Aluminum alloy

1.8

Brass

2.3

Cast iron

3.5

Resistance against Dent

Magnesium alloy has a high resistance against deformation and is less easily made dents than other metal.

 

Vibration absorption

Magnesium alloy can absorb vibration energy effectively.This is a desirable property for applications which any mechanical movement is expected.


Application: Slide base for optical pick-up, and electric fan

 

Ductility

A certain kind of magnesium alloy has a higher ductility than aluminum alloys and can absorb impact energy without brittle fracture.


Application: Steering wheels and seat flames for automobiles

 

Dimensional Stability

Dimensions of magnesium parts are very stable against time and temperature.

 

Easy Recycling

Magnesium can be recycled without any degradation in physical properties,which is often experienced in plastics recycling. Also, the energy necessary for recycling process of magnesium alloys is smaller than that for other metals. Only 4% of energy for virgin metal production is enough for recycle process of used magnesium alloy.

 

Comparison of Characteristics of Each Material

NAME Density
(g/cm³)
Melting
temperature
(°C)
Thermal
conductivity
(W/Mk)
Tensile
strength
(MPa)
Yield
strength
(MPa)
Elongation
(%)
Specific
strength
Young's
modulus
(GPa)
Magnesium
alloy
(Thixomolding™)
AZ91 1.82 596 72 280 160 8 154 45
AM60 1.79 615 62 270 140 15 151 45
Aluminum
alloy
(die casting)
380 2.7 595 100 315 160 3 117 71
Steel Carbon steel 7.86 1,520 42 517 400 22 66 200
Plastics ABS 1.03 90(Tg) 0.2 35 * 40 34 2.1
PC 1.23 160(Tg) 0.2 104 * 3 85 6.7