On the origin of the anomalous compliance of dealloying-derived nanoporous gold

TL;DR

This paper investigates the unexpectedly high compliance of nanoporous gold by comparing molecular dynamics and finite element simulations, revealing microstructural influences and nonlinear elastic effects.

Contribution

It provides a comparative analysis of MD and FEM models to explain the anomalous compliance of nanoporous gold, highlighting the role of microstructure and nonlinear elasticity.

Findings

Both models show higher compliance than Gibson-Ashby predictions.

FEM predicts stiffer response than MD, indicating nonlinear elasticity effects.

Microstructural features beyond porosity influence compliance.

Abstract

The origin of the anomalously compliant behavior of nanoporous gold is studied by comparing the elasticity obtained from molecular dynamics (MD) and finite element method (FEM) simulations. Both models yield a compliance, which is much higher than the predictions of the Gibson-Ashby scaling relation for metal foams and thus confirm the influence of other microstructural features besides the porosity. The linear elastic FEM simulation also yields a substantially stiffer response than the MD simulation, which reveals that nonlinear elastic behavior contributes decisively to the anomalous compliance of nanoporous gold at small structure size.