A thermo-mechanical framework for analysis of grain size evolution during high temperature creep

Benjamin Holtzman (1) , André Chrysochoos (2) , Loïc Daridon (3)

1 LDEO - Lamont-Doherty Earth Observatory
2 ThM2 - ThermoMécanique des Matériaux
3 M3 - Modélisation Mathématique en Mécanique

We develop a theoretical description of high temperature creep with microstructural evolution. The model considers non-linear thermodynamics of irreversible processes (TIP), accounting for dissipated energy associated with creep processes and microstructural changes, as well as energy stored in the microstructure. The" Generalized Standard Materials"(GSM) formalism used here allows for strong coupling among multiple processes through the use of free energy (Helmholtz) and dissipation potentials that are functions of mechanical, thermal and internal or structural state variables. We represent dislocation density and grain size as the structural state variables, to which energy dissipation and storage are associated. We develop two versions of the model, the first with only the grain size and the second with both dislocation density and grain size.

Domaines: Mécanique des matériaux [physics.class-ph]

Benjamin Holtzman, André Chrysochoos, Loïc Daridon. A thermo-mechanical framework for analysis of grain size evolution during high temperature creep. AGU Fall Meeting, Dec 2013, San Francisco, United States. ⟨hal-02057357⟩