Tensile properties of long aligned double-walled carbon nanotube strands

The mechanical properties of well-aligned double-walled carbon nanotube (DWNT) strands with diameters of 3-20mum and lengths of similar to10mm were measured using a stress-strain puller. The average tensile strength and Young's modulus of the tested strands are 1.2GPa and 16GPa, respectively. Deformation and fracture processes of these samples are discussed. The tensile strength and Young's modulus of an individual DWNT bundle were estimated, with values comparable to those of SWNT bundles. The superior mechanical strengths of our as-prepared DWNT strands are expected to give them potential as a high-strength material and a reinforcement in composites. (C) 2004 Elsevier Ltd. All rights reserved.