Nonlinear elasticity of monolayer graphene

TL;DR

This paper combines continuum elasticity theory and atomistic simulations to derive the nonlinear stress-strain relation for monolayer graphene, providing insights into its elastic behavior and failure properties.

Contribution

It presents the first comprehensive calculation of nonlinear elastic moduli for graphene, interpreting recent experiments and predicting the effective nonlinear elastic modulus.

Findings

Good agreement with experimental data on nonlinear elastic modulus

Observation of hyperelastic softening behavior

Insights into failure properties of graphene

Abstract

By combining continuum elasticity theory and tight-binding atomistic simulations, we work out the constitutive nonlinear stress-strain relation for graphene stretching elasticity and we calculate all the corresponding nonlinear elastic moduli. Present results represent a robust picture on elastic behavior of one-atom thick carbon sheets and provide the proper interpretation of recent experiments. In particular, we discuss the physical meaning of the effective nonlinear elastic modulus there introduced and we predict its value in good agreement with available data. Finally, a hyperelastic softening behavior is observed and discussed, so determining the failure properties of graphene.