Anisotropic sintering shrinkage in alumina ceramics containing oriented platelets

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

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, cilt.89, sa.6, ss.1972-1976, 2006 (SCI-Expanded, Scopus)

Özet

The effect of oriented alpha-Al2O3 platelets on densification and shrinkage behavior of tape-cast alpha-Al2O3 during solid-state sintering was studied using dilatometric sintering shrinkage experiments and microstructural characterization. Platelet-free alumina samples exhibit isotropic shrinkage with an similar to 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 similar to 12% in the casting and the transverse directions and similar to 20% in the direction perpendicular to the casting plane.