Reliability evaluation of Carbon-Nanotube-Reinforced-Polymer composites based on multiscale finite element model

Abstract

Experimental investigations to study the material behavior of nanocomposites have limitations. Hence, computational modeling and simulation encompassing multiscale material behavior provide an alternate approach to study the mechanical properties of such materials. The objective of the present work is to develop a computational framework for performing a probabilistic analysis of a Carbon-Nanotube-Reinforced-Polymer (CNRP) material by using the stress-strength model to determine the reliability and hazard associated with its mechanical properties, in terms of its longitudinal elastic modulus and ultimate longitudinal strength. A 3D multiscale finite element model of the Representative Volume Element of the nanocomposite consisting of a polymer matrix, an imperfect Single-Walled-Carbon-Nanotube (SWCN) and an imperfect interface region has been constructed for this purpose. The polymer matrix is modeled with the Mooney-Rivlin strain energy, the imperfect SWCN is modeled as a space frame structure using the Morse potential, and the interface region is modeled via van der Waals (vdW) links. In practical applications, the SWCN is not perfect, and it possesses structural defects, and moreover, the vdW links are not perfect. Such imperfections are characterized using the Monte Carlo simulation technique. The reliability and Hazard functions of the CNRP material are calculated using the Maximum Entropy Method.