Absorbing technique

For several years researchers have been investigating carbon nanotubes in search of the properties they can give composites. Strength, semiconducting ability and ability to carry extra materials have all been examined, but a team from

has now found another possibility — vibration damping.

The finding could be used across a wide range of applications such as space research, sporting equipment, car engines, and audio equipment, according to lead researcher Nikhil Koratkar. The technique could be particularly useful because nanofibres tend to add strength as well, unlike traditional damping additives which are soft.

The key to the property, Koratkar and colleagues explain, is the way polymers slip against nanotubes in a composite. The 'slip-stick' friction at the interface between polymer and nanotube — where the shear force applied builds up until it reaches a certain value, at which point the materials 'slip' against each other — allows the material to absorb the energy of the vibration.