A Phenomenological Constitutive Equation

Deformation Mechanism of Fine-Grained Superplasticity in Metallic Materials Expected from the Phenomenological Constitutive Equation

The superplastic behavior of fine-grained metals is well described by the deformation model in which grain boundary sliding (GBS) is accommodated by slip. This slip accommodation process involves the sequential steps of glide and climb, with climb assumed to be the ratecontrolling process. The climb distance during GBS is often considered to be on the order of grain size in the conventional the...

Constitutive Equation Gap

Micro-electromechanically Informed Phenomenological Constitutive Models for Ferroelectrics

Accurate phenomenological constitutive laws for ferroelectric ceramics that can be rapidly integrated are required for finite element models aiming to resolve the complex fields in ferroelectric devices. At best, phenomenological theories can provide a framework within which thermodynamic restrictions are satisfied and undetermined functions exist for “fitting” material behavior. The ultimate c...

A Constitutive Model for Sands

In this paper, an elastoplastic constitutive model is presented for predicting sandy soil behavior under monotonic and cyclic loadings. The model is based on the CJS3 model that takes into account deviatoric and isotropic mechanisms of plasticity. The flow rule in deviatoric mechanism is non-associated and a kinematic hardening law controls the evolution of the &#10yield surface. In the present...

First-principles constitutive equation for suspension rheology.

Using mode-coupling theory, we derive a constitutive equation for the nonlinear rheology of dense colloidal suspensions under arbitrary time-dependent homogeneous flow. Generalizing previous results for simple shear, this allows the full tensorial structure of the theory to be identified. Macroscopic deformation measures, such as the Cauchy-Green tensors, thereby emerge. So does a direct relati...