A thermodynamic based constitutive model considering the mutual influence of multiple physical fields

Area of Science:

• Materials Science
• Thermodynamics
• Continuum Mechanics

Background:

• Mutual influence of physical fields impacts material elastoplasticity.
• Existing models often treat field characteristics as adjustable parameters.

Purpose of the Study:

• Develop a thermodynamic-based constitutive model for coupled physical fields.
• Incorporate mutual field influences via a thermodynamic dissipation potential.

Main Methods:

• Formulate a generalized thermodynamic model using Onsager reciprocity relations.
• Degrade the model for AA5182-O AlMg alloy under temperature and strain rate coupling.
• Utilize a thermodynamic dissipation potential to describe plastic flow.

Main Results:

• The model accurately captures the plastic flow stress of AA5182-O AlMg alloy.
• It demonstrates distinct strain rate effects on flow stress at low and high temperatures within the Portevin-Le Chatelier regime.

Conclusions:

• The proposed model effectively integrates mutual physical field influences.
• It provides a scalable framework for developing constitutive models for diverse materials and coupled fields.