Modeling anisotropic single crystal growth kinetics in liquid phase sintered ?-Al2O3

Abstract

Single crystals of ?-alumina with {0001}, {11¯20} and {01¯12} orientations were embedded in a matrix of liquid phase sintered alumina to study ?-alumina single crystal growth in the presence of a calcium aluminosilicate liquid. Growth on the {11¯20} and {01¯12} surfaces was observed to occur by a diffusion-controlled mechanism while growth on the basal surface was controlled by two-dimensional nucleation. Growth models, which incorporate the change in matrix grain size, were derived and shown to fit the growth kinetics.