Influence of discontinuities on the fracture behaviour of CNT reinforced composites subjected to thermo-mechanical load using XIGA

Abstract

This paper is aimed to investigate the fracture behaviour of carbon nanotube (CNT) reinforced composite exposed to the thermo-mechanical environment in the presence of discontinuities using the extended isogeometric analysis (XIGA) method. The study focuses on finding the effects of discontinuities present in a finite plate with a pre-existing crack, on the stress intensity factors (SIFs). The mandatory equivalent mechanical and thermal properties are assessed with the help of various micromechanics models. Two types of CNTs are assumed to be reinforced in the epoxy-matrix: single-walled carbon nanotube (SWCNT) and multi-walled carbon nanotube (MWCNT). The CNT reinforced composite is examined for varying volume percentages of CNTs reinforcement. A comparative study is provided to see the influence of mechanical and coupled thermo-mechanical load on SIFs. Adiabatic crack is taken into account for the computational simulation for thermal loading condition. The interaction integral method is used for the extraction of SIFs. The findings of the test reveal that with the rise in the volume percentage of CNTs, the properties such as fracture energy and fracture toughness also rise. Moreover, the fracture of CNT reinforced composites is delayed with the increased content of CNT. The results establish the profound influence of holes on SIFs than the inclusions.