Electromechanical response and failure behaviour of aerogel-spun carbon nanotube fibres under tensile loading

The effect of tensile loading on the mechanical and electrical behaviour of carbon nanotube fibres spun continuously from an aerogel is discussed. While these fibres exhibit moderate strength (0.19 GPa) and elastic moduli (9.16 GPa), their piezoresistive behaviour, evaluated through active resistance measurements during tensile loading, demonstrates their potential for sensing applications in advanced composite materials. Insight into the failure behaviour of the aerogel-spun fibres is gained through microscopic examination of the failed fibres, as well as analysis of their electrical response. A new phenomenon for carbon nanotube fibres is reported-the aerogel-spun fibres are observed to undergo mild to severe kinking due to tensile failure. This kinking is attributed to compressive failure due to recoil from the fibre free ends. A simple analysis of experimental results yields a fibre compressive strength range of 172-177 MPa.