A Multiphysics Thermoelastoviscoplastic Damage Internal State Variable Constitutive Model including Magnetism.

Area of Science:

• Multiphysics modeling
• Continuum mechanics
• Materials science

Background:

• Existing constitutive models lack interdependence between magnetic and mechanical fields.
• Previous models primarily focused on nanoscale structure-property relations for magnetic-induced deformations.

Purpose of the Study:

• To present a fully coupled multiphysics macroscale Internal State Variable (ISV) model.
• To integrate magnetic effects with thermal, elastic, plastic, and damage phenomena.
• To incorporate lower length scale information into a macroscale framework.

Main Methods:

• Developed a macroscale constitutive model using ISV theory.
• Employed multiplicative decomposition of the deformation gradient, including a magnetization term.
• Utilized the first and second laws of thermodynamics and the Clausius-Duhem inequality.
• Implemented a kinetic framework with a coupled stress-strain relationship and flow rule.

Main Results:

• The model captures magnetic field forces with isotropic and anisotropic magnetization terms.
• It accounts for thermomechanical deformations by integrating magnetic effects.
• ISV modeling framework coheres kinematic, thermodynamic, and kinetic relationships.
• Demonstrated good correlations between model predictions and experimental data for iron, nickel, and cobalt.

Conclusions:

• The presented ISV modeling framework offers a novel approach to couple magnetism with mechanical and thermal effects.
• This macroscale model successfully integrates nanoscale and microscale physics.
• The model provides a robust tool for understanding and predicting the behavior of magnetic materials under complex loading conditions.