Particle Orientation Distribution in Alumina Compact Body Prepared by the Slip Casting Method

摘要

The packing structure of particles is studied for alumina compact made by slip casting,with an emphasis placed on the local orientation of particles.The orientation is visualized and analyzed quantitatively using an optical method,which is based on the measurement of optical anisotropy using a polarized microscope.In the measurement,the compact is soaked in an immersion liquid to make it transparent,and is observed by a crossed polarized optical microscope to determine the retardation of the compact with a compensator.The degree of particle orientation is defined as the ratio of birefringence of the compact and that of alumina single crystal.The degree of particle orientation is found to be 3-9%.The structure of the compact is found to have a close relevance to the draining direction of slurry in casting.