Strain rate-dependent tensile properties and dynamic electromechanical response of carbon nanotube fibers

This investigation into the rate-dependent tensile behavior of carbon nanotube (CNT) fibers provides insight into the role of strain rate and specimen gage length on tensile strength. Chemical vapor produced CNT continuous fibers made of single and dual wall CNTs are evaluated and the potential for fiber improvement by post-process stretching to improve alignment is explored. Post-processed CNT fibers exhibit significantly higher strengths (3–5 GPa) and moduli (80–200 GPa) than untreated fibers. During dynamic tension evaluation, real-time electrical measurements provide correlations between high rate deformation/damage mechanical behavior and electrical resistance of the fiber specimens. Furthermore, this first look into the dynamic tensile behavior of CNT fibers demonstrates their potential to serve as sensors in high rate applications.