Where Magnesium comes from
Magnesium is the eighth most abundant element in the earth’s crust. While not found in metallic form, it is broadly available in the form of minerals such as magnetite, dolomite and serpentine. It has a silvery-white colour and tarnishes slightly in air.
Magnesium metal has unique characteristics. It has the lowest density of all the metal elements, making it the lightest, but is also very strong and easily manipulated for machine tooling. Magnesium has similar characteristics to its sister metal, aluminum, but is 34% lighter than aluminum, and 70% lighter than steel, making it a solution of choice for lightweight requirements in the transportation industry.
Figure 1: shows the breakdown of magnesium usage in different applications around the world in 2012.
Figure 2: shows the weight saving potential for a magnesium automotive part with the same functionality as one made of aluminium, light steel or steel.
In addition to an excellent density / tensile strength ratio, magnesium enjoys additional interesting characteristics:
- Because of its crystalline arrangement, magnesium has an excellent capacity to reduce vibration transmission;
- Magnesium is more fluid than aluminium and can therefore fill a complex mould much more easily during casting operations. It can also form thinner parts, saving additional weight for a given part;
- Magnesium offers excellent electromagnetic shielding properties. A 1-mm thick wall reduces electromagnetic transmission by 80%;
- Last but not least, magnesium is less aggressive on steel moulds than aluminum, ensuring a longer tool lifetime.