Anisotropic sintering shrinkage in alumina ceramics containing oriented platelets


Ozer I., Suvaci E., Karademir B., Missiaen J., Carry C., Bouvard D.

Journal of the American Ceramic Society, vol.89, no.6, pp.1972-1976, 2006 (SCI-Expanded) identifier

Abstract

The effect of oriented α-Al2O3 platelets on densification and shrinkage behavior of tape-cast α-Al2O 3 during solid-state sintering was studied using dilatometric sintering shrinkage experiments and microstructural characterization. Platelet-free alumina samples exhibit isotropic shrinkage with an ∼17 linear final shrinkage. The addition of platelets retards densification, and results in anisotropic shrinkage. Initially during sintering, shrinkage is isotropic for platelet-containing systems; however, it becomes highly anisotropic by inhibition of shrinkage in the platelet orientation direction. In the 10 vol platelet-containing system, shrinkage was ∼12 in the casting and the transverse directions and ∼20 in the direction perpendicular to the casting plane. © 2006 The American Ceramic Society.