Yu Kuronuma

Numerical and experimental study on the response of multi-walled carbon nanotube/polymer composites under compressive loading

In this paper, we present the numerical and experimental characterisation of the compressive behaviour of multi-walled carbon nanotube (MWNT)/polymer composites. Compression tests were conducted on MWNT/ polymer composites at room temperature and liquid nitrogen temperature (77 K) to identify the effect of nanotube addition on their macroscopic behaviour. Multiscale analysis was also performed to predict the composite response to compressive loading. Three-dimensional finite elements were used to model the representative volume element (RVE) of MWNT/polymer composites, and the nanoscale structure of the MWNT was incorporated by determining its elastic properties using analytical molecular structural mechanics models. It was found that the elastic modulus in compression is improved effectively by adding MWNTs. The correlation between the numerical and experimental results presents some basic insights regarding the reinforcing mechanisms in the nanocomposites under compression.

Loading Rate-Dependent Fracture Properties and Electrical Resistance-Based Crack Growth Monitoring of Polycarbonate Reinforced with Carbon Nanotubes Under Tension

This paper presents a combined numerical-experimental study on the loading rate-dependent fracture behavior of cracked carbon nanotube (CNT)-based polymer composites under tension. Tensile tests at various loading rates were conducted on single-edge cracked plate specimens of CNT/polycarbonate composites. The electrical resistance change of the composite specimens was utilized to capture the crack behavior during the tests. An elastic-plastic finite element analysis was also employed to determine the fracture properties by means of the J-integral. In addition, scanning electron microscopy (SEM) observation was implemented to assess the fracture mechanisms of the CNT-based polymer composites under the different loading rates.

Fatigue failure and electrical resistance behaviors of carbon nanotube-based polymer composites under uniaxial tension–tension loading in a cryogenic environment

This paper investigates the fatigue failure and electrical resistance behaviors of carbon nanotube-based polymer composites at cryogenic temperatures. Tension–tension fatigue tests were performed on carbon nanotube /polycarbonate composites at room temperature and liquid nitrogen temperature (77 K), and the electrical resistance of the specimens was monitored during the tests. Based on the obtained results, the dependence of the mechanical and electrical responses of the nanocomposites on the temperature and the nanotube content was studied. Microscopic examinations were also carried out on the specimen fracture surfaces, and the failure mechanisms of the nanocomposites were discussed.

Electrical and Crack Responses of CNT-Based Polymer Composites Under Tension

This paper studies the electrical and mechanical responses of cracked carbon nanotube (CNT)-based polymer composites. Tensile tests were conducted on single-edge cracked plate specimens at room temperature and liquid nitrogen temperature (77 K), and the electrical resistance change of the specimens was monitored. An analytical model was also developed to predict the resistance change resulted from crack propagation. In addition, the fracture properties of the nanocomposites were evaluated in terms of the J-integrals from an elastic-plastic finite element analysis.Copyright

BENDING RESPONSE OF CARBON NANOTUBE‐BASED POLYMER COMPOSITES AT CRYOGENIC TEMPERATURES

This work examines the cryogenic bending response of carbon nanotube (CNT)‐based polymer composites through experiments and multiscale simulations. Flexural tests on CNT/polycarbonate composites were performed at cryogenic temperatures. Multiscale analysis was also performed to predict the composite behavior at cryogenic temperatures. The variations of the mechanical response with the interfacial damage state were discussed, and the simulation results were utilized to understand the experimental observations.