The deformation behavior of a metallic sheet material as a polycrystalline solid structure is closely related to its statistical average crystallographic orientation characteristics as well as other characteristics, such as chemical composition and microstructure. The precise measurement of bulk texture, the crystallographic orientation distribution characteristics, is of most importance not only to optimize the production process of metallic materials, weaken the earring phenomenon during deep drawing deformation, improve the final commercial value of products, but also to provide the relative material information for materials scientists to develop the numerical plastic deformation models or related theories and establish the internal relationship between plastic deformation behavior and crystallographic orientation characteristics. However, there is no ISO standard specification on how to realize a precise texture measurement up to now.
If I understood the question right, the columnar mosaic structure can be evaluated by rocking curve technique. But this structure is sample dependent and is sensitive to the preparation conditions.
Yes, there should be a set of bulk standards. Especially considering the loss of information in the diffraction experiment. As I aware, there are some 'hand-made' ones: e.g., http://www.labotex.com/standards-info.pdf
I think standards on texture are required. Such standards can greatly help the young researchers
In 1990s, Prof. H.R. Wenk made a Round Robin Test with some limestone using neutron diffraction. His results said that good reliability can be obtained using neutron diffraction. (JOURNAL OF APPLIED CRYSTALLOGRAPHY, 28(1995): 503-507). While for X-ray diffraction, the corrections are dependent on the target materials and sample surface characteristics. So it seems easy to make a simple standard specification using neutron diffraction.
Recently, there were measurements of the same material on HIPPO (Los Alamos) and SKAT (Dubna) neutron TOF diffractometers: doi:10.1016/j.tecto.2012.06.023. It was the same material (a rock - biotite gneiss), but two different samples. A smaller one was for HIPPO due to its sample size limitations, while on SKAT where luminosity is much lower it is possible (and so much advantageous) to measure bigger (about 100 cm^3) sample. Results published in paper are quantitatively different for the biotite, which has the sharpest texture. Yet there were additional experiments on HIPPO (unpublished) with the same sample, but with different pole figure coverage, and then results were looking much more like these from SKAT. So even with neutron texture diffractometers things like solid angles that are 'seen' by each detector, pole figure coverage, sufficient counting statistics, low background, absorption corrections in case of irregular sample shapes should be considered... At least when dealing with complex/multiphase materials and/or sharp textures...
In Japan, we have two angle dispersive neutron diffractometers and two time-of-flight neutron diffractometers upgraded or being upgraded for the necessary texture measurements. We hope to do something to improve or confirm our texture evaluation reliablity.
There is always a variant to do the 'round-robin' thing once again. Not with one sample, but maybe with three: single phase/weak texture, single phase/sharp texture, multi (2-4) phase. Spherical samples, a few centimeters in diameter, homogeneous, grains of around 10 micron size, rather good scatterers... Maybe include different setups of the same diffractometer, different data analyzing software... Maybe prepare something analogous to compare with synchrotron/EBSD...
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