Hybrid hierarchical model for damage and fracture analysis in heterogeneous material

Abstract

Complex materials with heterogeneities and discontinuities is a focus of current research in materials science and engineering because such materials promise to have superior properties including enhanced mechanical strength and fatigue resistance. Predictive damage and fracture analysis of complex materials is grueling since it involves the modeling of highly-coupled nonlinear processes at disparate scales. A logical approach taken by many researchers in tackling this challenge is to employ a framework that couples Molecular Dynamic (MD) and Finite Element (FE) modeling in some manner to capture damage processes occurring at different time and length scales. Unfortunately, such coupling typically suffers from the lack of thermodynamic consistency between the MD and FE models and causes pathological wave reflection that commonly occurs at the interface between the MD and FE simulation regions. This work endeavors to circumvent those problems by introducing a Hybrid Hierarchical Model (HHM) that consists of an MD module with an ab initio based force field and a peridynamic continuum mesoscale module. The HHM framework was applied to perform the fracture modeling of a silicon carbide slab with pre-crack and the high-cycle fatigue damage analysis of a turbine blade.