About this Abstract |
Meeting |
2024 ASC Technical Conference, US-Japan Joint Symposium, D30 Meeting
|
Symposium
|
2024 ASC Technical Conference, US-Japan Joint Symposium, D30 Meeting
|
Presentation Title |
Predicting Fracture Toughness in Polymer Nanocomposites using Concurrently Coupled Atomistic-Continuum Simulations |
Author(s) |
Sankha Subhra Aditya, Mohammad Din Al Amin, Samit Roy |
On-Site Speaker (Planned) |
Sankha Subhra Aditya |
Abstract Scope |
Graphene nanoplatelets (GNP), dispersed in epoxy resins, have been reported to show remarkable improvements in fracture toughness. This work seeks to investigate the nanoscale mechanisms near the crack tip in the presence of graphene nanoplatelets that promote the improvement in fracture toughness. The size of the fracture process zone formed in epoxy near a crack, typically on the order of tens of microns, is beyond the range of pure molecular dynamics (MD) modeling. Hence, MD simulations, concurrently coupled with finite element method (FEM) to bridge length scales, are used to simulate the crack initiation behavior under fracture loading. A novel concurrent multiscale coupling methodology is used, that partitions the full simulation domain into MD and FEM subdomains, and iteratively computes solutions for a given load step. The nonlinear behavior in the MD domain is approximated in the FEM domain using a Ramberg-Osgood constitutive model, parameterized based on MD representative volume elements (RVE). K-dominant displacement fields, derived from linear elastic fracture mechanics (LEFM) are used as boundary conditions, away from the crack tip and surrounding the fracture process zone (FPZ). Stresses and strains in the MD domain (near-crack-tip region) will be compared at a given level of far-field loading for baseline specimens and GNP-embedded specimens. The goal is to be able to predict fracture toughness at crack initiation at room temperature. The effect of GNP orientation, GNP size, and volume fraction on the fracture toughness will be investigated and the crack initiation fracture toughness quantified using the atomistic J-integral. |
Proceedings Inclusion? |
Definite: Post-meeting proceedings |