Another day, another material that could lead to lighter vehicles of the future. The latest candidate? Magnesium.

Magnesium componentry in cars is nothing new of course. Magnesium alloy wheels are popular in the motorsport world where light weight and impressive strength are paramount. Now, researchers in Germany believe that it could be used in greater capacity throughout vehicle construction.

To prove it, they're showing a magnesium door at the Hannover Messe, an annual trade fair for innovative technology in Germany. The magnesium door weighs about 10 lbs, where a standard steel door would weigh nearer 23.5 lbs. Shedding half the weight isn't an insignificant achievement and it's easy to see the weight of an average car plummeting, and the larger the car, the greater the gain.

Why magnesium? "Magnesium is available in large quantities worldwide, it can be moulded, and for similar structures - a car door, for instance - it has virtually the same properties as steel. For example, it has a comparable rigidity" explains Sören Scheffler, group manager of the Fraunhofer AutoMOBILE Production Alliance, the team who developed the door.

So will we see magnesium bodies before long? As with other lightweight technologies, it's likely to depend on production costs. Carbon fiber is attracting a lot of attention for its light weight and strength, but current methods of production are expensive and time consuming so cars with carbon monocoques tend to be expensive. Aluminum too is lightweight but hard to construct cars from, and save for a few Audis and Jaguars is not widely used.

That magnesium is plentiful is a positive sign, likewise the ease of which it can be moulded. Rather than replacing any current technology, it's likely to be one of many materials used in coming years to reduce the weight of our cars, to the benefit of performance, handling and above all, fuel economy.

[Cordis, Fraunhofer]