Constitutive modeling of spark-plasma sintering of conductive materials

A constitutive model for spark-plasma sintering (SPS) taking into consideration various mechanisms of material transport is developed. The contributions of sintering stress (surface tension), external load, and electromigration to sintering shrinkage are jointly analyzed. It is shown that electromigration-related material flux can be a significant component of the electric-current-accelerated diffusion. A spark-plasma sintering mechanism transport map is designed for aluminum powder. The results of modeling agree satisfactorily with the experimental data on Al powder’s SPS in terms of shrinkage kinetics.