The sintering behavior of close packed spheres
  The sintering behavior of close packed spheres is investigated using a numerical model. The investigated systems are the body centered cubic (BCC), face centered cubic (FCC) and hexagonal closed packed spheres (HCP). The sintering behavior is found to be ideal with no grain growth until full density is reached for all systems. During sintering the grains change shape from spherical to tetrakaidecahedron, similar to the geometry analyzed by Coble (R. L. Coble, J. Appl. Phys. 32 (1961) 787). 
R. Bj{\o}rk, V. Tikare, H. L. Frandsen and N. Pryds
cond-mat.mtrl-sci cond-mat.mes-hall physics.comp-ph