Open Access
Subscription or Fee Access
Modeling the Effect of Nanoparticle Size on Fracture Toughness of Nanocomposites
Abstract
The objective of this paper is to investigate the validity of application of continuum-based linear elastic fracture mechanics (LEFM) methodology, which is often employed by researchers to model fracture processes at the “discrete†atomic scale. The material selected for this study is EPON 862 epoxy polymer with 85% cross-link density. Further, an atomistic J-integral is implemented as a nano-scale fracture metric to investigate flaw-tolerance at the nanoscale reported by many researchers, and to develop a methodology to predict the initiation fracture toughness of the material. For this purpose, a bond-order based potential (ReaxFF) available in LAMMPS molecular dynamics (MD) software is utilized. Predictions obtained using the atomistic J-integral are compared with LEFM predictions for the case of a crosslinked epoxy polymer block with a center-crack under uniform far-field loading. Significant deviations from LEFM for crack-lengths below a certain critical cracklength threshold are observed. Further, far-field stress-strain plots are obtained for a center-cracked epoxy polymer block with a graphene nanoplatelet embedded ahead of the crack tip and compared with stress-strain plot obtained for neat baseline epoxy
DOI
10.12783/asc35/34936
10.12783/asc35/34936