Carbon nanotube films change Poisson’s ratios from negative to positive

摘要

In this paper, a discovery is reported that carbon nanotube u0002CNTu0003 films can change in-planenPoisson’s ratios from negative to positive during a uniaxial tensile loading. First, in situnexperimental investigations of the deformation fields about the CNT films fabricated using verticallynaligned CNT arrays are performed by digital speckle correlation method, the novel phenomenon fornchanging Poisson’s ratio from negative to positive during the stretching process is discovered.nFurthermore, the physical mechanisms for changing the Poisson’s ratio from negative to positive arenexplained based on the interactions among CNTs. Finally, a potential engineering application forndesigning intelligent connector is proposed based on the intriguing Poisson’s ratio of CNT films.n© 2010 American Institute of Physics. u0004doi:10.1063/1.3479393