Mixed mode properties of CNT reinforced composites using Arcan test rig

Abstract

Composite materials reinforced with carbon nanotubes were mechanical tested using Arcan test rig under Mode-I, Mode-II and mixed mode loading conditions to obtain their fracture properties. The butterfly composite specimens were fabricated with 0.02, 0.05 and 0.1 wt % CNTs. The polyester/CNT composite was fabricated using VRTM (Vacuum Resin Transfer Molding) where the CNTs were first functionalised to reach an optimum properties. Arcan test rig was designed and fabricated to work with the Shimadzu testing machine. The results show that the functionalised CNTs have improved the fracture behavior by acting as bridge between the cracked face. In addition, the fracture properties were not improved for the higher weight fraction of 0.1 wt% CNTs.

Keywords

CNT / composites / Arcan test rig / stress intensity factor

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Acknowledgements

The author acknowledges the financial support from the DST-NRF Centre of Excellence in Strong Materials, housed in the School of Physics at the University of the Witwatersrand, the National Research Foundation (NRF), South Africa, in particular the Nanotechnology Flagship Programme.

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg