Concurrent Multiscale Framework for Wave Propagation in Crystalline Material Nanostructures

Abstract Nanoscale defects, such as micro-voids and grain boundaries, critically influence the mechanical properties of microscale and nanoscale structures. Wave propagation analysis serves as a powerful tool to investigate these properties, offering valuable insights into the presence and characteristics of defects without damaging the structure. Traditional modeling methods to study dynamics of nanoscale structures like Molecular Dynamics are computationally expensive, requiring significant computational resources with increasing domain sizes and simulation times. This research introduces an innovative concurrent multi-scale framework that integrates atomistic and continuum modeling approaches for wave propagation studies in crystalline nanos-tructures. The framework couples the Quasicontinuum method — applied for fine-scale subdomains that potentially harbor defects — with the Spectral Finite Element Method (SFEM) to efficiently conduct accurate wave propagation studies. Using atomistic simulations, material information is extracted for coarse-scale subdomain modeled using SFEM model. Direct Coupling at atomistic-continuum interface ensures stable wave propagation is achieved without any undesirable effects or additional computational overhead. This work offers a promising avenue for the efficient and accurate modeling of transient dynamics of crystalline material nanostructures, with potential applications in materials design, non-destructive testing, and failure analysis.