Observation of the Fine Structure of 7-Alumina Using Electron Microscope

Abstract

The fine structure of γ-alumina prepared by different procedures was observed by electron microscope. The specimens were prepared by ultra thin sectioning method to preserve their fine structure.
It has been found that the method of preparation of r-alumina affects its fine structure significantly. JRC-ALO-1 alumina is composed of two kinds of crystallites: filamentous and columnar ones in outer and inner parts, respectively. The shape of their aggregates is the same as that of its raw material (Fig.1). JRC-ALO-4 alumina has a simple texture. Most crystallites have same size and shape (Fig.4). JRC-ALO-5 alumina is spherical granule, which consists of filamentous r-alumina covered with well crystallized r-alumina (Fig.5).