Determination texture fraction in Fe-doped alumina substrates used for production of carbon nanotubes

Polycrystalline materials are formed of an aggregate of single crystal grains. Grains in polycrystalline materials are usually randomly oriented. If the crystallographic orientations between the grains are not random, but have some preferred orientation, the sample has a weak, moderate or strong texture and their properties depend on the amount of texture. Texture in materials can be characterized by using different techniques, such as x-ray diffraction (XRD) and transmission electron microscopy (TEM) based techniques but the most powerful and effective technique is a scanning electron microscope (SEM) based electron backscattered diffraction (EBSD) technique which is useful for obtaining crystallographic information in the SEM at submicron resolutions. It allows the determination of relationship between grains as well as morphology and the chemistry of grains. The purpose of this study is to reveal the degree and quality of texture in iron doped alumina ceramics produced by TGG technique which are utilized as substrates for CNT growth. The goal of this work is to determine the degree of texture in iron doped alumina ceramics for the first time by using EBSD technique, hence to determine best conditions for production and for sample preparation techniques of high quality textured iron-doped ?-Al2O3 ceramics for CNT growth. As a result, in alumina ceramic substrates, which contain liquid phase and 10wt% iron doped alumina exhibit the best orientation of all.Keywords: EBSD, electron diffraction, textured materials, orientation, crystallography