Magnesium has a specific gravity of 1.74 compared to aluminium 2.70, titanium 4.51 and steel 7.87. Magnesium provides a huge advantage to wheels where
being ‘lightweight’ is crucial.
[Enhanced acceleration/deceleration performance and steering response]
1. As is well known, the lighter the outer periphery of a rotating element, the less force that is required for rotating and stopping the rotating element.
The rotation speed is also a contributory factor. There is not much difference in weight between the magnesium wheel and the aluminium wheel, but because
the gravity of the outer periphery (rim) of the magnesium wheel is 3/5 of that of the aluminium rim, this provides enhanced acceleration/deceleration
performance and quick steering response, benefitting not only from less gravity by 3/5 of the gravity of the aluminium wheel but also from increased
rotation efficiency by several folds.
2. A decrease in the unsprung weight reduces the stretch amount of a spring (suspension), thus, suppressing vibrations much better. This also makes the
load shift smoother when cornering or reducing the speed, ensuring steady driving without unstable behaviour.
[Fuel saving and CO2 reduction]
An increase in the wheel diameter reduces the tyre weight while reducing the unsprung weight. There is not much difference in weight between the magnesium
wheel and the aluminium wheel, but because the gravity of the outer periphery (rim) of the magnesium wheel is 3/5 of that of the aluminium rim, this
increases the rotation efficiency by several folds. A reduction of the unsprung weight by 1 kg is equivalent to a reduction in the sprung weight by as much
as 15 kg, which contributes to saving fuel and reducing emission of CO2.
Wheel materials must be lightweight while providing rigidity; being light is just not good enough. Magnesium has a specific strength (= tensile strength /
specific gravity) of 15, which is far superior to steel 5, and aluminium 9.
Magnesium is more recyclable than plastic. When burnt, magnesium generates fewer impurities and less static electricity (less likely to attract
impurities). Magnesium is also a metal that is easy to return to the original state.