A thermodynamically consistent phase‐field model for viscous sintering

A thermodynamically consistent phase‐field model for viscous sintering is proposed. It is based on an energetic variational formulation that allows the governing equations to be analytically derived from a defined energy law. The conservation of mass is satisfied through the incompressibility assumption and the assumption that mass density is uniform initially within the particle compact while the balance of linear momentum is formulated from an energy dissipation law. The morphological changes of particles are described by the temporal and spatial evolution of a phase‐field variable governed by a modified Cahn‐Hilliard equation, and the motion of viscous mass flow is controlled by the Stokes equation incorporating the surface tension effect. The application of the phase‐field model is illustrated by examining the effect of particle shape, initial contact angle and rearrangement effects on viscous sintering.