Experimental tests on fracture strength of nanotubes

A new experimental and post-analysis procedure to perform tensile-loading experiments on nanofibers, e.g., carbon nanotubes (CNTs) or nanowires, is presented. The procedure has been applied to multiwalled carbon nanotubes (MWCNTs). At this time, we consider the corresponding results on fracture strength (strain and Young's modulus) as preliminary, but these preliminary results strongly suggest the presence of defects in the tested nanotubes. Assuming defects like clusters of adjacent vacancies (e.g., atomistic blunt cracks) we tried to rationalize the preliminary experimental data by applying Quantized Fracture Mechanics (QFM). So far the experimental results are not sufficient to validate this approach, and the next step of this research is to obtain much more data, using our new methodology, to further test QFM, including possibly introducing atomistic defects of well-known size and shape in a controlled way.