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Two series of zirconium samples were investigated by neutron and X-ray diffraction. First series of the samples was deformed at room temperature (RT), whereas the second series was deformed at 300 °C. Both series were deformed on uniaxial tensile machine INSTRON 5882 from strain 0 to 30% (strain step was 5%). The neutronographic texture measurements were performed on the KSN-2 neutron diffractometer located at the research reactor LVR-15 in the Nuclear Research Institute, plc. Rez, Czech Republic. The X-ray measurements were performed at the theta/theta X'Pert PRO diffractometer with the Cr X-ray tube. Observed data were processed by the software packages GSAS and X'Pert Texture. Preferential orientation of the $\left({10\bar 10} \right)$ and $\left({11\bar 20} \right)$ plane poles is found to be parallel to the rolling direction for both tested deformation series. Poles of the $\lpar 10\bar 12\rpar $ and $\lpar 10\bar 13\rpar $ planes tend to be parallel to the normal direction (Tables II and III). Orientation of the basal poles is tilted by 45° from the normal direction toward the transverse direction. Sharpness of the resulting texture increases with extends of the applied deformation as well as with rise of the tensile test temperature from the RT level to 300 °C. [ABSTRACT FROM AUTHOR]

Neutron diffraction (ND) was used to investigate the crystallographic preferential orientation (CPO, texture) and structure parameters of four samples of metagabro mylonite collected from the eastern part of the metagabbro sheet at the Stare Mesto belt, Bohemia Massif, Czech Republic. The samples were selected to form a deformation-ordered series with the microstructure varying from non-deformed metagabbro protolith to strongly sheared ultramylonite and amphibole-rich ulramylonite. The specimens used in ND measurements were polished in form of an exact sphere with diameter 50 ± 0.1 mm. The obtained ND patterns were corrected for non-linear background and then evaluated using the Rietveld method implemented in the software package GSAS. Data recorded from powder preparded by milling material from the sampled rocks were used to refine the structure parameters of plagioclase (labradorite structure, triclinic space group C-1) and amphibole (monoclinic space group C2/m). The experiments were performed on the KSN-2 neutron diffractometer situated at the research reactor LVR-15 of the Nuclear Research Institute, plc. Rez, Czech Republic. The data sets of ND patterns measured on each of the four spherical specimens consisted of 90 diagrams collected for different diffraction vectors covering uniformly one orientation hemisphere of the specimen. Based on the collected data, the orientation distribution function (ODF) of crystalline grains was determined by Rietveld harmonic method (coefficients C(l,m,n) of the spherical harmonics expansion determined up to the order L = 8) for the two principal mineral phases - amphibole and plagioclase. The ODF was used to reconstruct (001), (020), (021), (110), (111) (plagioclase) and (001), (11-1), (020), (110), (200) (amphibole) pole figures (PFs). Direct method of ODF calculation implemented in ResMat software package was then used to calculate inverted pole figures (IPFs) of the plagioclase phase. CPO of the amphibole and plagioclase is then discussed in terms of the obtained texture indices and calculated PFs and IPFs and compared with data measured by other methods or available in literature. [ABSTRACT FROM PUBLISHER]