Equilibrium conditions at a solid-solid interface

Abstract

We derive the thermodynamic conditions necessary for two elasto-plastic solid phases to coexist in equilibrium. In doing so, we examine the well-known case of inviscid fluids and note the underlying physical principles so that we apply them to the case of solids. Beyond temperature, velocity, and traction continuity, these conditions require continuity of a generalization of the specific Gibbs free energy. We express this quantity in the Eulerian frame, as well as the Lagrangian frame. We also show that two approaches in deriving the equilibrium conditions, one on the continuum level and the other on the atomistic scale, yield the same results. © 2012 American Institute of Physics.