A Large Strain Isotropic Elasticity Model Based on Molecular Dynamics Simulations of a Metallic Glass

作者：Henann David L; Anand Lallit^*

来源：Journal of Elasticity, 2011, 104(1-2): 281-302.

DOI：10.1007/s10659-010-9297-y

• Finite elasticity
• Logarithmic strain
• Molecular dynamics

For an isotropic hyperelastic material, the free energy per unit reference volume, psi, may be expressed in terms of an isotropic function psi = (psi) over bar (E) of the logarithmic elastic strain E=ln V. We have conducted numerical experiments using molecular dynamics simulations of a metallic glass to develop the following simple specialized form of the free energy for circumstances in which one might encounter a large volumetric strain tr E, but the shear strain (with E (0) the deviatoric part of E) is small but not infinitesimal: This free energy has five material constants-the two classical positive-valued shear and bulk moduli mu (0) and kappa (0) of the infinitesimal theory of elasticity, and three additional positive-valued material constants (mu (r),epsilon (r),epsilon (c)), which are used to characterize the nonlinear response at large values of tr E. In the large volumetric strain range -0.30a parts per thousand currency signtr Ea parts per thousand currency sign0.15 but small shear strain range numerically explored in this paper, this simple five-constant model provides a very good description of the stress-strain results from our molecular dynamics simulations.

• 出版日期2011-8