Orientation Imaging Microscopy of Alpha Alumina: Sample Preparation and Texture Analysis

Orientation imaging microscopy (OIM) was used to study hot isostatically pressed (HIP) 99.99 % α-Al . A sample preparation procedure for nonconducting ceramics and a preliminary texture analysis are given. The sample preparation procedure was optimized to produce a thin conductive coating, a smooth well polished and at the same time nearly strain free surface. In these alumina samples, the grain area ranged from 350 to 4000 μm . Several grains exhibited a [0001] orientation with misorientation angles between two adjacent grains near 60°. From contour inverse pole figures, a slight texture, two times random, was determined along the sample “rolling direction” [100] which corresponded to the extrusion direction of the green body.