Directional solidification of CoO-ZrO2 eutectics

Abstract The directional solidification of CoO-ZrO 2 eutectic with and without Y 2 O 3 has been investigated by the floating zone melting method. A directionally solidified structure without cell structure can be grown for both CoO-ZrO 2 and CoO-ZrO 2 -Y 2 O 3 eutectics. The dominant growth morphology in these eutectics was the lamellar structure. The interface of the lamella has the orientation relationship of (001)cubic ZrO 2 ⌈(111)CoO and steps with periodic spacing. This relation at the interface was retained even if the ZrO 2 phase was transformed to the monoclinic phase from the cubic phase through the tetragonal structure.