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Revised on 10 January 2018
crystallographic texture of the solid, hereinafter briefly crystal texture
or texture, is understood to mean the statistical entity of the
crystallite orientations in a polycrystal. In the narrower sense, however,
one often means the deviations from the statistical randomness of
orientations, or in other words, the presence of preferred orientations.
In bulk multi-crystalline materials, preferred orientations are in general
regularly linked to the process of structure formation, such as
solidification, nucleation, grain growth, recrystallization, phase
transformation, sintering, plastic deformation. For powders, ceramic green
compacts and sediments, preferred orientations often arise as a
consequence of form anisotropy from (needle or platelet-shaped)
crystallites in the starting material.
Texture analysis was originally based on the
interpretation of pole figures, which in most cases were measured by X-ray diffraction.
In further development, X-ray diffraction was supplemented by neutron
diffraction for the highest relevance of the measurement and electron
diffraction for highest spatial resolution. The measurement of pole figures is carried out
by means of a texture goniometer. The texture goniometer makes it possible to adjust the Bragg angle
and thus select the diffractive type of lattice planes (hkl), as well as to rotate
the sample through the entire Ewald reference sphere, so that all directions of the sample can be brought into reflection
position. A comprehensive account of the
initial period until 1962 can be found in the German monograph "Text
uren metallischer Werkstoffe (Textures of Metallic Materials)"
by G. Wassermann and J. Grewen.
using a Scanning X-ray Apparatus or, recently, by individual grain
orientation measurement in electron microscopes (e.g. EBSD and TKP), the
information from texture analysis can be combined with the microstructure
map of the material in real space to a comprehensive understanding known
as Orientation Microscopy and finally Orientation Stereology.
This website crystaltexture.com provides
a survey of the development of
• Pole figure measurement
by selected area electron diffraction in the TEM (SAD)
grain orientation measurement by evaluating transmission Kikuchi patterns
• Measurement and mapping of local texture with a Scanning
X-Ray Apparatus (SXA).