On the Irreversible Deformations Growth in the Material with Elastic, Viscous, and Plastic Properties and Additional Requirements to Yield Criteria

At present study the closed mathematical model of the deformation processes of materials with elastic, viscous and plastic properties under large deformations is developed. The reversible and irreversible determinations of components are given by the differential equations of change (transfer). The stress-strain equations are derived by the thermodynamic potential independence hypothesis on irreversible deformation. The irreversible deformations accumulation is modelled without discrimination of creep and plastic parts. During unloading process the reverse consequence of the dissipative mechanisms is assumed. The irreversible deformations and rates continuity conditions are provided by the plastic potential specification (yield criterion). The developed approach is illustrated by examples. In virtue of proposed approach the boundary value problems for cylinder under pressure gradient and viscometric deformations are solved.