Russian researchers at Siemens Corporate Technology are using special carbon nanoparticles to optimise materials. They are adding fullerenes – football-shaped molecules comprising 60 carbon atoms – to aluminium to obtain a new material that is roughly three times harder than conventional composites, yet weights much less. The lightweight yet strong aluminium could be used to improve the performance of compressors, turbochargers and engines.

The pure-carbon fullerenes have high mechanical stability at a low weight. Aluminium and C60 are ground under an argon atmosphere into tiny grains with a diameter of just a few nanometres (millionths of a millimetre). The two substances then bond with each other to form the new material. Special mills are used to grind the aluminium.

The ultrafine powder is pressed together to form a new material. Roughly one per cent by weight of fullerenes suffices to give the material sufficient hardness. Siemens envisages a variety of applications for the hard aluminium. Turbines with lighter rotors can deliver higher speeds and make compressors or engines more efficient. One could coat superconducting cables with the material to improve their stability. They would then be able to withstand stronger currents, which in turn would make machines such as magnetic resonance tomographs more powerful. Because fullerenes barely affect the electrical conductivity of the aluminium, aluminium electric cables could be made thinner to save material.