Fine structure of plastically deformed carbon nanotube

The mechanical properties and the fine structure of plastically deformed carbon nanotube were examined by transmission electron microscopy (TEM). The carbon nanotube discovered by Iijima in 1991 is Like a whisker crystal so that an extremely high tensile strength and the lack of plasticity are generally predicted. The in-situ observation performed in TEM, however, proved that the carbon nanotube is not brittle but bends plastically at room temperature. High resolution electron microscopy of the fine structure showed that the deformation is a series of bucklings in the compressive side of the cylindrical network of carbons. The fine structure is simulated by both the network models of carbon atoms and molecular mechanics calculation. The deformed structures lead us to a new concept of fiber material with ideal mechanical properties. The process, however, assumes that the buckling may be reversibly eliminated.